LAS VEGAS (AP) — The latest on the Democratic presidential debate at the Wynn hotel in Las Vegas (all times local):

8:40 p.m.

Republican presidential front-runner Donald Trump isn’t impressed by his Democratic rivals’ performance during their first debate.

The billionaire businessman and showman has been offering his commentary via Twitter.

He describes the debate “a little sad!” and says the candidates seemed too scripted and rehearsed.

He has especially harsh words for the lower-polling candidates.

He says there’s “no way” anyone can imagine former Rhode Island Gov. Lincoln Chafee as president and thinks former Maryland Gov. Martin O’Malley “has very little chance.”

On former Virginia Sen. Jim Webb, he retweeted someone asking, “Why is Webb there??”

He concludes, “Sorry, there is no STAR on the stage tonight!”

8:35 p.m.

One bold-name Democrat was completely absent from the first Democratic presidential debate: Joe Biden.

The vice president had been expected to be the elephant in the room as he continues weighing whether to enter the primary.

But not one of the five candidates onstage mentioned his name, nor were they asked how his entrance would alter the race.

Speculation about a potential late-entrance by Biden was so high that debate host CNN had an extra podium on hand for him just in case.

But Biden stayed back at his official residence in Washington to watch the debate on television.

7:59 p.m.

Former Maryland Gov. Martin O’Malley is using his 90-second closing to rail on the Republicans, mocking their two debates as lessons in intolerance.

He says of his Democratic colleagues: “What you heard tonight (was a) different debate than the sort of debate you heard from the two presidential Republican debates.”

The Republican debates so far have involved far more than the five people onstage Tuesday in Las Vegas — so many that they have been divided into two tiers.

O’Malley used the turmoil within the Republican ranks to make the point that Democrats were more unified in their goals, saying, “I truly believe that we are on the threshold of a new era of American progress.”

7:56 p.m.

Legalizing pot isn’t exactly a hot topic for Democrat candidates at their first debate Tuesday night.

Hillary Clinton says she supports medical marijuana use but isn’t ready to take a position on recreational marijuana, a year after she said she would wait to see how it played out in Washington and Colorado.

Bernie Sanders says that if he were a Nevada voter considering legalizing recreational marijuana use next year, he suspects he would vote for it — but mainly because he thinks the war on drugs and the criminal justice system need to be entirely reworked.

7:53 p.m.

Hillary Rodham Clinton is lashing out at what she calls Republican hypocrisy on abortion.

She says the GOP wants to reduce the role of big government in people’s lives. But that’s not the case with social issues like abortion.

The Democratic front-runner says: “They don’t mind having big government to interfere with a woman’s right to choose and to try to take down Planned Parenthood. They’re fine with big government when it comes to that. I’m sick of it!”

The comments produced loud cheers during the first Democratic presidential debate Tuesday night.

Republicans in Congress and in the presidential race have repeatedly tried to strip funding from Planned Parenthood, a woman’s health care provider that offers abortions.

7:51 p.m.

Vermont Sen. Bernie Sanders says the only way to take on Republicans is for workers to come together.

Sanders says, “The only way we can get things done is by having millions of people coming together.”

He says if workers want the minimum wage to be increased to $15 an hour, they have “look Republicans in the eye” and tell them to take action or be voted out of office.

7:50 p.m.

Hillary Rodham Clinton is stressing that she’s different from the rest of the Democratic 2016 candidates — emphasizing that she’d be the first Madame President.

Clinton’s role as the lone female Democratic candidate provided a brief moment of levity after a commercial break, when CNN moderator Anderson Cooper thanked the candidates for returning quickly to the stage. Referring presumably to a bathroom break, Clinton quipped: “You know, it does take me a little longer. That’s all I can say.”

7:49 p.m.

When it comes to climate change, former Virginia Sen. Jim Webb was the odd man out on the Democratic debate stage.

Webb says he backs an “all of the above energy policy” — including coal, nuclear and the construction of the Keystone XL pipeline. Asked about climate change, Webb stresses the role China and India play and says the issue must be addressed as a global problem.

Webb’s competitors are promising more aggressive action on climate change.

Former Maryland Gov. Martin O’Malley says his first executive order would set a target for a 100 percent clean electric grid by 2050.

Vermont Sen. Bernie Sanders says he agrees with Pope Francis that climate change is a “moral issue.”

Hillary Clinton claims she’s already been working on the issue. She says that as secretary of state, she and President Obama pushed the Chinese to enter into an agreement to reduce greenhouse gases.

7:47 p.m.

Maryland Gov. Martin O’Malley is the first to say another Clinton in the White House is one too many.

He says to Clinton, whose husband was president that “we cannot be this dissatisfied” with the nation’s politics and economy “and think that a resort to old names is going to move us forward.”

It’s a question the Republicans also face, with Jeb Bush — the son and brother of former presidents — also seeking the White House.

Clinton says: “I certainly am not campaigning for president because my last name is Clinton. I’m campaigning because I think I have the right combination of what the country needs.”

7:45 p.m.

Hillary Rodham Clinton is sidestepping a question about whether immigrants in the country illegally should receive federal health care subsidies. But she says they should receive in-state college tuition.

The Democratic front-runner says such immigrants should be able to buy into health-care exchanges created by President Barack Obama’s health-care overhaul. She says going any further would raise too many issues and should be addressed in a broader immigration bill.

Immigration is a key issue in the 2016 presidential contest. Clinton’s comments came during the first Democratic presidential debate Tuesday night.

Clinton says Republicans have demonized and insulted immigrants in recent months. Most of the Democrats favor giving immigrants in the country illegally a pathway to citizenship.

Clinton also says such immigrants should receive in-state college tuition so long as state leaders agree.

7:38 p.m.

How would their presidencies be different from President Barack Obama’s?

Hillary Rodham Clinton says, “Being the first woman president would be quite a change from the presidents we’ve had up until this point, including President Obama.”

Vermont Sen. Bernie Sanders says he would lead a “political revolution” bringing together millions of people to transfer power from large corporations to the working class.

Former Maryland Gov. Martin O’Malley says he would combat recklessness on Wall Street.

Former Rhode Island governor and senator Lincoln Chafee says he would stop wars in the Middle East and former Virginia Sen. Jim Webb says he would reduce the president’s use of executive authority.

7:37 p.m.

Former Secretary of State Hillary Clinton is suggesting she disagrees with Sen. Bernie Sanders’ plans to expand Social Security.

She says she “fully” supports Social Security and “the most important fight we’re going to have is defending it against continuing Republican effort to privatize it.”

Clinton’s comments at the Democratic debate came in response to a question about some of Sanders’ pricier policy proposals, including plans to significantly increase payments to Social Security recipients.

Sanders says the plan would be paid for if top earners were asked to pay more in payroll taxes.

Clinton says she and Sanders “agree on the goals, we just disagree on the means.”

She says wants to enhance Social Security benefits for the poorest recipients and “focus on helping those people who need it the most.”

7:35 p.m.

Hillary Rodham Clinton and Martin O’Malley agree that Edward Snowden, who exposed widespread NSA surveillance programs and fled to Russia, could have been protected as a whistleblower but broke the law instead.

“Whistleblowers do not run to Russia,” O’Malley, the former Maryland governor, said during the first Democratic debate.

Sen. Bernie Sanders, grateful to Snowden for exposing what happened, says Snowden should get a break for educating the public. But he agrees Snowden should be penalized for breaking the law.

As of January 2014, a CBS News poll showed 61 percent of Americans, including 64 percent of Democrats, thought Snowden should have to stand trial rather than be granted amnesty.

Lincoln Chafee isn’t one of them. The candidate says he should be brought home. Jim Webb is leaving it up to the legal system.

7:33 p.m.

One of the clearest differences between Hillary Clinton and Bernie Sanders comes during a discussion of the Patriot Act. Clinton is for it. Sanders is not.

Clinton says there’s a fine line between protecting the homeland and protecting civil liberties and individual rights.

She says the Patriot Act “was necessary to make sure we were able after 9/11 to put in place the security we needed,” but “we have to balance the of civil liberties privacy and security.”

Sanders says flatly, “I would shut down what exists right now.”

“Every telephone call in the country ends up in a file,” he says. “The government is involved in our emails.”

Finally, he says, “There are ways to (be free) without impinging on our privacy right.”

7:20 p.m.

Jim Webb says he “wouldn’t have a problem” with undocumented immigrants receiving health benefits under the Affordable Care Act.

During the first Democratic debate, the former Virginia senator is stressing that the United States should define its borders and must pursue comprehensive immigration reform. He notes that his wife is originally from Vietnam.

“Her family escaped from Vietnam on a boat,” Webb says. “She went to two refugee camps, she never spoke English in her home and she ended up … graduating from Cornell Law School. … That’s the value that we have with a good immigration system.”

7:15 p.m.

Lincoln Chafee has plenty of excuses for why he voted to repeal a Depression-era law banning financial institutions from combining their commercial banking operations with riskier investment banking:

He had just arrived in Congress.

It was his first vote as a senator from Rhode Island.

His dad had died in office.

He was appointed.

Chafee ticked them all off during the Democratic presidential debate when asked to explain his 1999 vote repealing the law known as Glass-Steagall.

Chafee says: “Glass-Steagall was my very first vote. I’d just arrived. My dad had died in office. I was appointed to the office. It was my very first vote.”

The awkward exchange came after Hillary Rodham Clinton and Vermont Sen. Bernie Sanders called for tougher oversight of Wall Street.

7:05

Vermont Sen. Bernie Sanders says the measure enacted in 2008 to bail out investment banks did not go far enough.

He says, “The greed and reckless behavior of Wall Street, where fraud is a business model, helped to destroy this economy and the lives of millions of people.”

Sanders says, “We have got to break them up.”

Hillary Rodham Clinton says she supports continued monitoring of the banks under current law, but she sympathizes with the anger at bank officials.

She says, “I represented Wall Street as a senator from New York, and I went to Wall Street in December of 2007, before the big crash that we had, and I basically said, cut it out.”

Clinton also is acknowledging more needs to be done.

6:55 p.m.

Bernie Sanders says “black lives matter.”

The Vermont senator addressed the nation’s racial challenges during the first Democratic presidential debate. He faced criticism from African-American activists earlier in the year for his response to the “black lives matter” movement.

He was asked Tuesday night whether “all lives matter” or “black lives matter.” He responded, “Black lives matter.”

Sanders says the nation must combat “institutional racism from top to bottom.” He’s also calling for major reforms to the nation’s criminal justice system. He says the U.S. has more people in jail than China — and a disproportionate number of them are minorities.

Sanders comes from one of the whitest states in the nation. He remains relatively unknown among many black voters, who play an important role in Democratic politics.

6:50 p.m.

Former Secretary of State Hillary Clinton and Vermont Sen. Bernie Sanders agree: Enough with the emails.

Sanders passed on the chance to pounce on his political rival’s Achilles’ heel in the Democratic debate Tuesday night. He says he knows it may not be good politics, but “the American people are sick and tired of hearing about your damn emails.”

Clinton and the crowd cheered the moment. She turned to Sanders, shook his hand and said, “Thank you, Bernie.”

Clinton says the debate over her use of a private email server as secretary of state is being ginned up by Republicans. She says she made a mistake, but the committee investigating the matter is “basically an arm of the Republican National Committee.”

She says she’d rather talk about health care, student debt and issues that affect voters.

6:45 p.m.

Hillary Rodham Clinton says American diplomats know the risks when they take assignments in dangerous regions.

The former secretary of state briefly addressed diplomatic security when asked during the first Democratic presidential debate about the 2012 attack in Benghazi, Libya. Ambassador J. Christopher Stevens and three other Americans were killed in the siege. Republicans have spent years investigating Clinton’s role in the attack.

Clinton says, “When we send them forth, there is always the potential for danger and risk.”

She also defends U.S. actions in the country before the attack: “We did not put one single American soldier on the ground in Libya.”

Clinton’s Democratic opponents declined to criticize her position on Benghazi.

6:42 p.m.

Hillary Rodham Clinton had a quick comeback for an attack from Martin O’Malley — touting his 2008 endorsement of her previous presidential bid.

During the first Democratic presidential debate Tuesday night in Las Vegas, the former Maryland governor criticized the 2002 decision to authorize the war in Iraq, which Clinton voted in favor of, calling it “one of the worst blunders in modern American history.” Clinton has more recently called her vote in favor of the war a “mistake.”

O’Malley also questioned her support for a no-fly zone in Syria.

Clinton shot back saying she “was very pleased when Gov. O’Malley endorsed me in 2008 and enjoyed his strong support in that campaign,” she said.

6:40 p.m.

Gun laws have emerged as an important issue in the Democratic presidential debate. Polls show Democrats are largely united on the subject, even as Americans as a whole are more ambivalent. A CBS News poll conducted in July and August found that 77 percent of Democrats, but just 52 percent of Americans overall, said gun laws should be made stricter.

But Americans are united on one gun policy proposal. A July Pew Research Center poll showed that 85 percent of Americans, including 87 percent of those in gun-owning households, support requiring background checks for private sales at gun shows — a fact that former Secretary of State Hillary Clinton referred to during the debate.

Democrats are especially unlikely to think that more guns make people safer. In the Pew Research Center poll, 59 percent of Democrats said gun ownership puts people’s safety at risk. In comparison, just 36 percent think it protects people’s safety.

6:38 p.m.

Martin O’Malley says Hillary Clinton’s preference for a no-fly zone in Syria would be a mistake.

“I think we have to play a long game,” the former Maryland governor says of Syria.

O’Malley is also using the opportunity to condemn the vote to go to war in Iraq under “false pretenses,” calling it “one of the worst blunders in modern American history.” O’Malley says he believes lawmakers were railroaded by polls. He referenced a John Quincy Adams quote that warned against searching the world for monsters to destroy.

6:35 p.m.

Vermont Sen. Bernie Sanders says the U.S. should deploy ground troops only when the United States or an ally is attacked.

He says he is “not a pacifist,” but believes “in my heart war should be the last resort. I am prepared to take this country into war if necessary.”

He says he supported U.S. force in 2001 against the Taliban in Afghanistan after the Sept. 11 attacks. He also supported U.S. force in Kosovo under President Bill Clinton to fight against ethnic cleansing.

But Sanders continues to lament Hillary Rodham Clinton’s support for the U.S. invasion of Iraq in 2003.

Sanders says, “I heard the same evidence from President Bush” about Iraq, and decided to vote against the invasion.

6:32 p.m.

Vermont Sen. Bernie Sanders says the U.S. invasion of Iraq is the “worst foreign policy blunder in the history of the country.”

Sanders says Iraq is a quagmire and he will make sure the country never gets involved in anything like it again.

Hillary Rodham Clinton voted to invade Iraq when she was in the Senate in 2002. She has since called that vote a mistake.

Clinton says she also withstood repeated criticism for that vote during the 2008 Democratic presidential debates, but President Barack Obama still trusted her enough to name her as secretary of state.

6:25 p.m.

Former Secretary of State Hillary Clinton says she would “take more of a leadership position” and stand up to Russian President Vladimir Putin over Syria.

Asked during the Democratic debate about Russia’s increasing involvement in the Syrian civil war, Clinton says she would take a harder line against Putin. She says, “we have to stand up to his bullying” and “make clear” that Russia has to be part of the solution.

Clinton’s comments were her first criticism during the debate of her former boss, President Barack Obama.

Clinton also says she would create “safe zones” to try to ease the massive refugee crisis destabilizing the region.

6:23 p.m.

Hillary Rodham Clinton is going after Bernie Sanders on guns.

She says the Vermont senator wasn’t tough enough “at all” on gun violence while in the Senate. He voted for a 2005 measure to give gun manufacturers immunity from lawsuits.

The issue sparked a heated exchange during the opening minutes of the first Democratic presidential debate.

Sanders says the immunity issue was complicated.

Clinton says she was in the Senate at the same time, and “it wasn’t complicated to me.”

Sanders says he supports expanded background checks for gun owners and closing the “gun show loophole.” He’s highlighting his D-minus rating with the National Rifle Association. He adds that he comes from a rural state, where attitudes about gun ownership are different than urban states.

6:15 p.m.

Former Maryland Gov. Martin O’Malley is defending his record despite the unrest this year in Baltimore, where he served as mayor before his two terms in Annapolis.

He says he “didn’t make our city immune to setbacks,” but says “we saved over 1,000 lives in Baltimore in the last 15 years and the vast majority of them were young and poor and black.”

O’Malley goes on to note that he enacted gun legislation in Maryland “by leading with principle, not by pandering to the NRA.”

O’Malley identified in the audience the family of a victim of the Aurora, Colorado, movie theater shooting in 2012.

6:10 p.m.

Former Secretary of State Hillary Clinton is defending capitalism — and going after her most serious opponent in the process.

Vermont Sen. Bernie Sanders describes himself as a Democratic socialist, and in Tuesday’s debate he has praised countries like Denmark for their protection of workers.

When the candidates were asked by debate moderator Anderson Cooper if they agree with Sanders’ view, Clinton was quick to chime in. She says when she thinks about capitalism “I think about the all the small businesses.”

Clinton concedes that every so often capitalism needs to be saved from itself but “our job is to rein the excesses of capitalism.”

6:09 p.m.

Bernie Sanders is kicking off his first debate answer by listing some of his favorite countries — Denmark, Sweden and Norway.

The self-proclaimed Democratic socialist says all three nations are examples of places that provide for working people. Sticking with his progressive campaign message, Sanders is railing against a system in the United States that he says benefits the very wealthy.

Democratic front-runner Hillary Rodham Clinton seized on the comments from her top opponent in the race, saying capitalism can also help small businesses. “We are not Denmark. I love Denmark. We are the United States of America,” she proclaimed.

Sanders shot back that business growth is meaningless if it only benefits the “top 1 percent.”

6:08 p.m.

Lincoln Chafee says his views on the issues haven’t changed, even though his political affiliation has.

The former Rhode Island governor and senator is a former Republican and independent. Now, when he’s running for president, Chafee says he’s a “proud Democrat.”

In the first Democratic debate, Chafee says despite those changes in political affiliation, on policy he is a “block of granite.”

He says, “I have not changed on the issues.”

Chafee says the Republican Party left him and there was no room for a liberal moderate in the GOP.

6:05 p.m.

Hillary Rodham Clinton is immediately defending changing her position on the Trans-Pacific Partnership trade agreement last week.

She says, “Like most human beings, I do absorb new information.”

Clinton adds that she had hoped the agreement would be “the gold standard,” but in the end says “it didn’t meet my standard.”

Asked whether she is a “progressive” or “moderate,” she describes herself as a “progressive” with “a long history of getting things done.”

6:04 p.m.

Hillary Rodham Clinton says economic fairness for the middle class is the centerpiece of her campaign for president.

She’s promising to raise the minimum wage and push companies to share profits with their workers.

She also offered a message directly to women in her opening statement: “Fathers will be able to say to their daughters, you too can grow up to be president.”

6:02 p.m.

Vermont Sen. Bernie Sanders is appealing to the middle class in his opening debate comments, saying the top 1 percent is thriving while regular Americans are working longer hours for lower wages.

He is also calling for campaign finance reform to curb the influence of the wealthy, combating climate change and spending more on education and jobs for young people to keep them out of jail.

5:58 p.m.

Former Maryland Gov. Martin O’Malley says his executive experience makes him the best leader.

He is citing his work pushing to raise the minimum wage, promoting gay marriage and advancing gun safety legislation as he introduces himself at the first Democratic debate. O’Malley says his work is evidence that he know how to get things done and is “very clear” about his principles.

5:52 p.m.

Former Virginia Sen. Jim Webb is emphasizing his “record of working across the political aisle” in his opening statement, while promoting his national security credentials.

He says he “fought and bled” for his country in the Vietnam War as a Marine and later served as the secretary of the Navy in the Reagan administration. He is calling for a “common sense” foreign policy to keep the nation safe.

5:50 p.m.

The Democratic debate is underway with opening statements.

The first statement comes from former Rhode Island Gov. Lincoln Chaffee, who reviewed his resume and boasted of having no scandals while in office.

5:40 p.m.

CNN is broadcasting the debate live to virtual reality headsets.

Partnering with company NextVR, the network is making the views available to some 100,000 people who possess an Oculus-made Gear VR headset that works with specific Samsung smartphones.

Not everything will be visible, though. Viewers won’t see the notes the candidates are writing on the pads of paper on their podiums. NextVR’s post-production director Timothy Amick says its cameras were specifically positioned far enough away to not get a peek at the scribbles.

5:30 p.m.

President Barack Obama is trying to rally Democrats before the party’s first presidential debate.

The president spoke to the party faithful via a video aired before the faceoff. He cited progress, like the legalization of gay marriage, that has occurred since his election.

The president asked Democrats to “work even harder” in this election cycle to ensure he is replaced by a Democrat next year.

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4:40 p.m.

Nevada Sen. Harry Reid is giving no inkling of which Democratic presidential candidate he plans to support, calling the participants in Tuesday’s debate “five of my friends.”

Reid says he expects the debate to be substantive. It’s the first of six scheduled Democratic debates, a number Reid said he was satisfied with during a press conference a few hours earlier.

Reid also facetiously apologized for saying Iowa and particularly New Hampshire are not representative of how the rest of America will vote because no one lives there and there are no minorities. He made the remarks Monday at a pre-debate event.

“New Hampshire is terribly populated and loaded with lots of minorities,” Reid said Tuesday.

Census data shows New Hampshire’s 1.3 million people are 94 percent white.

4:20 p.m.

One of the most talked-about Democrats in the 2016 race won’t even be on stage.

Vice President Joe Biden plans to watch the debate from the Naval Observatory, his official residence in Washington. Biden’s office says he’s also hosting a high school reunion earlier in the evening.

Biden is months into serious deliberations about whether to join the Democratic field. It’s unclear what role the outcome of Tuesday’s debate will play in his decision.

The vice president had a light schedule Tuesday in Washington, but made an unannounced stop at the Turkish Embassy to sign a condolence book honoring the 97 people killed in weekend bombings in Ankara.

Biden’s decision could come at any time, but his schedule for Wednesday is already jam-packed. The White House says he’ll attend President Barack Obama’s daily briefing in the Oval Office, speak at a White House summit on infrastructure investment, and meet with Obama and Secretary of State John Kerry. He’ll also have lunch in private with Obama.

4:10 p.m.

An October 2007 memo circulated by President Barack Obama’s campaign advisers says Hillary Rodham Clinton was vulnerable to attacks on her character and Obama was better positioned to represent change.

The memo, reported by The New Yorker hours before Tuesday’s Democratic presidential debate, says in blunt terms that Clinton couldn’t be “trusted or believed when it comes to change” and is “driven by political calculation not conviction.” The memo also argues that Clinton embodies “trench warfare vs. Republicans” and is someone who has worked the system rather than change it.

It’s unclear if Clinton is still vulnerable to those attacks. But at least one member of her team is well aware of the arguments.

One of Clinton’s first hires was Joel Benenson, who was Obama’s pollster and one of the authors of the memo. He’s now one of Clinton’s top campaign strategists.

3:55 p.m.

Republican presidential frontrunner Donald Trump says he’ll be live-tweeting the Democratic debate, and he expects it to be “a very boring two hours.”

Democratic frontrunner Hillary Rodham Clinton responded, saying, “Glad you’ll be watching. It’s going to be ‘huge.‘”

Another Republican contender, Kentucky Sen. Rand Paul, is also getting in on the action.

He’s been live-streaming his day on the campaign trail and will be offering his reaction to the Democrats’ first faceoff on video.

Trump said Monday he expected most viewers to tune in to the debate for a few minutes and then fall asleep.

He’s also expecting low ratings for CNN compared with the record-breaking audiences his faceoffs with fellow Republicans have drawn.

3:50 p.m.

Supporters of rivals Hillary Clinton and Bernie Sanders clashed in a friendly faceoff on a crowded pedestrian bridge in Las Vegas ahead of Tuesday’s debate.

Wearing blue shirts, Clinton supporters are chanting “Madam President.” Opposing them: red-shirt-wearing registered nurses yelling, “Equal rights, jobs that pay, Bernie’s best for the USA.”

In the middle were several trapped Las Vegas tourists.

Jim Shilling, a 74-year-old tourist from La Crosse, Wisconsin, certainly didn’t mind.

“I love it. There’s enthusiasm. Democrats need enthusiasm,” he said. “I’m with ‘em both.”

3:45 p.m.

The Democratic candidates for president are making their final preparations for their party’s first debate of the 2016 race for the White House.

The candidates and their staffs are on-site at the Wynn hotel in Las Vegas, taking walkthroughs of the debate hall and preparing for what’s expected to be a policy-heavy confrontation.

Huma Abedin (HOO‘-muh AB‘-uh-deen), a top adviser to front-runner Hillary Rodham Clinton, has tested out the candidate’s podium at center stage.

Sen. Bernie Sanders also tested out his spot, and former Maryland governor Martin O’Malley took a moment to get a feel for the debate hall.

Also onstage will be former Sen. Lincoln Chafee of Rhode Island and former Sen. Jim Webb of Virginia.

Not on stage: Vice President Joe Biden, who is considering joining the contest and is said to be watching the show from home.

The debate begins at 6 p.m. Pacific time on CNN.