Tammy Suzanne Green Baldwin (born February 11, 1962) is the junior United States Senator from Wisconsin and a member of the Democratic Party. She previously served as the U.S. Representative from Wisconsin's 2nd congressional district from 1999 to 2013, as well as serving three terms in the Wisconsin Assembly representing the 78th district.Baldwin defeated her Republican opponent, former Wisconsin governor Tommy Thompson, in the 2012 U.S. Senate election.