Republicans have clinched a state Senate majority, four months before a single ballot is cast.

Eight Republican senators will be unopposed for reelection. Democrats filled four ballot vacancies ahead of Tuesday’s deadline, but even if they run the table in the November election, that would leave them with 24 seats, extending the Republican majority the party has held for 44 years.

Democrats would need to gain six seats to crack Republicans’ supermajority.

In the House, nearly half the 100 seats will be uncontested in November, with 29 Republicans and 13 Democrats assured of victory. Two more Republicans have write-in challengers but no opponents on the ballot, and one legislator in each party will have a one-on-one matchup with a Libertarian nominee. Democrats filled a dozen ballot vacancies for House races, while Republicans recruited two last-minute candidates of their own.

Parties have two months to add candidates if no one files for a race in the primary. Those 11th-hour additions usually go down to defeat in November, but Bloomington Democrat Peggy Welch served seven terms in the House after a late addition to the ballot in 1998. This year, the newly-recruited candidates include potentially competitive Republican-held seats in Zionsville and Carmel. Republicans have added candidates in districts which elected Republicans just six years ago, in Munster and West Lafayette, though redistricting has altered the contours of those seats.

Libertarians nominated candidates in four Indiana House districts.

Election officials have three steps left before finalizing the November ballot. While Libertarians can get on the ballot automatically, other third parties must gather petition signatures. The deadline to do so has passed, but third-party candidates have until next week to finalize their candidacies. So far, two independents have been placed on the House ballot.

After that deadline, the Indiana Election Commission must decide any challenges to candidates’ eligibility. And the Indiana Recount Commission still needs to resolve a recount of Hamilton County Councilman Fred Glynn’s six-vote victory for the Republican nomination in an open House seat. Glynn or challenger Suzie Jaworowski will face Democrat Victoria Wilburn in November.