Incumbent Democratic Senator Joe Donnelly lost re-election to a second term to Republican Mike Braun by a 6% margin.

In 2017, Politico described the race as "possibly the GOP's best opportunity to seize a Senate seat from Democrats" in the 2018 elections.

[2] 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%.

[4][5] Graphical summary with Todd Rokita with Luke Messer with generic Republican On November 6, 2018, Braun won the general election.

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.