Cynthia Marie Lummis Wiederspahn ( LUH-miss; born September 10, 1954) is an American attorney and politician serving as the junior United States senator from Wyoming since 2021. A member of the Republican Party, Lummis served as the U.S representative for Wyoming's at-large congressional district from 2009 to 2017. She served in the Wyoming House of Representatives from 1979 to 1983 and from 1985 to 1993, in the Wyoming Senate from 1993 to 1995, and as the Wyoming State Treasurer from 1999 to 2007. Lummis was elected treasurer of Wyoming in 1998 and reelected without opposition in 2002. She chaired Mary Mead's gubernatorial campaign in 1990 and Ray Hunkins's gubernatorial campaign in 2006. She also served on Bob Dole's presidential steering committee in Wyoming and chaired Mitt Romney's 2012 presidential campaign in Wyoming. Lummis unsuccessfully sought to be appointed to replace Senator Craig L. Thomas in 2007. She was elected to succeed Barbara Cubin in the U.S. House of Representatives in the 2008 election, defeating Democratic nominee Gary Trauner. During her tenure in the House, she was the first Wyoming representative to serve on the Agriculture Committee since 1941, chaired the Science Subcommittee on Energy, co-chaired the Congressional Caucus for Women's Issues, and was active in the Congressional Western Caucus and Freedom Caucus. She served until her retirement in 2017, and was succeeded by Liz Cheney. After her tenure in the House, Lummis sought a position in President Donald Trump's cabinet as Secretary of the Interior, but was not appointed. She was elected to the U.S. Senate in the 2020 election, becoming the first woman to represent Wyoming in the Senate. She voted to reject the certification of Pennsylvania's electoral votes in the 2020 presidential election, which were narrowly won by Joe Biden.