Republican Ann Wagner has won a third term in Congress representing suburban St. Louis.

The 54-year-old congresswoman defeated Democrat Bill Otto and Libertarian Jim Higgins on Tuesday. The district covers much of western and southern St. Louis County.

Wagner was first elected in 2012. She served as U.S. ambassador to Luxembourg under President George W. Bush. She's also a former Missouri Republican Party chairwoman and former co-chair of the Republican National Committee.