Jon Tester has served as the senior United States Senator from Montana since 2007. A third-generation Montana farmer, Tester grew up on his family's wheat and barley farm near the town of Big Sandy. He attended the University of Great Falls, earning a B.A. in music before returning home to work alongside his family on the farm.

Prior to entering politics, Tester taught music in elementary school in Big Sandy public schools and remained active in the family farming business. He first ran for the Montana State Senate in 1998, serving two terms before mounting a successful campaign for the U.S. Senate in 2006, winning with a margin of victory of less than 1 percent over a Republican incumbent. In 2018 he won in a state that voted for Trump by more than 20 points. Since arriving in Washington, Tester has built a reputation as a pragmatic, independent-minded Senator who focuses on issues important to rural Montanans.