Thune, John, 1961-

John Randolph Thune (/ˈθuːn/ THOON; born January 7, 1961) is an American politician and businessman serving as the senior United States senator from South Dakota, a seat to which he was first elected in 2004. A member of the Republican Party, he serves as Senate minority whip.

Thune has worked in politics and civic organizations since completing his MBA degree. He served in the U.S. House of Representatives for South Dakota's at-large congressional district from 1997 to 2003. Thune is known for his defeat of sitting Senate Democratic Leader Tom Daschle in 2004. In the United States Senate, Thune served as the Republican chief deputy whip from 2007 to 2009 and as chair of the Senate Republican Policy Committee from 2009 to 2012. He served as the Senate Republican Conference chair, the third-ranking position in the Senate, from 2012 to 2019.

The Senate Republican Conference selected Thune as majority whip for the 116th Congress; he succeeded Senator John Cornyn of Texas, who was term-limited in the position. In 2020, he was chosen as minority whip for the 117th Congress.