The 2018 United States Senate election in Indiana took place on November 6, 2018, along with other elections to the United States Senate and House of Representatives and various state and local elections. Incumbent Democratic Senator Joe Donnelly ran for re-election to a second term, however, he lost in the general election to Republican Mike Braun by a margin of 6%. This was the second consecutive election for this seat in which the incumbent was defeated and/or the seat flipped parties.
This was one of ten Democratic-held Senate seats up for election in a state won by Donald Trump in the 2016 presidential election. In 2017, Politico described the race as "possibly the GOP's best opportunity to seize a Senate seat from Democrats" in the 2018 elections. The primary election was held on May 8, 2018. In October 2018, RealClearPolitics rated the race a toss-up between the Democratic and Republican nominees, with the Libertarian receiving a poll average of 6%.
Instead of running for a second senatorial term in 2024, Braun campaigned successfully to become Governor of Indiana.
In 2012, Joe Donnelly was elected to the Senate with 50% of the vote to Republican nominee Richard Mourdock's 44%. In the 2016 presidential election, Republican nominee Donald Trump won Indiana with about 56.5% of the vote to Democratic nominee Hillary Clinton's 37.5%.
Graphical summary<br />
with Todd Rokita<br />
with Luke Messer<br />
with generic Republican<br />
On November 6, 2018, Braun won the general election. He swept southern Indiana, the exurbs of Indianapolis, and most other rural areas in the state. Donnelly ran well behind his 2012 vote totals, winning only in Indianapolis, the university centers (Bloomington, Terre Haute, West Lafayette, South Bend), and the suburbs of Chicago in Northwest Indiana.
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Braun won six of nine congressional districts, with Donnelly winning the other three, including one held by a Republican.
Official campaign websites