The 2012 United States Senate election in Montana was held on November 6, 2012, alongside a presidential election, other elections to the United States Senate in other states, as well as elections to the United States House of Representatives and various state and local elections. Incumbent Democratic Senator Jon Tester successfully ran for reelection to a second term, gaining 48.6% of the vote against Republican U.S. Representative Denny Rehberg who received 44.9% of the vote.