The 2010 United States Senate election in Wisconsin was held on November 2, 2010. Incumbent Democratic U.S. Senator Russ Feingold ran for re-election to a fourth term, but was defeated by Republican challenger Ron Johnson, a businessman and first-time candidate. Johnson was the first Republican to win a Senate election in Wisconsin since 1986. Feingold also became the fifth Senator in a row from Wisconsin's Class 3 Senate seat to be defeated for reelection in the general election, and the seventh in a row overall to lose reelection by a defeat in either the primary or general elections.