List of United States Senators from Wisconsin

Wisconsin was admitted to the Union on May 29, 1848. Its current senators are Republican Ron Johnson and Democrat Tammy Baldwin.

Class 1

Class 1 U.S. Senators belong to the electoral cycle that has recently been contested in 1994, 2000, 2006, and 2012. The next election will be in 2018.

Class 3

Class 3 U.S. Senators belong to the electoral cycle that has recently been contested in 1998, 2004, 2010, and 2016. The next election will be in 2022.

As of October 2016^[update], there are three living former Senators, one from Class 1 and two from Class 3. The most recent senator to die was William Proxmire of Class 1 (1957-1989) on December 15, 2005. The most recent Class 3 senator to die was Gaylord Nelson (1963-1981) on July 3, 2005.

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