Defeating his Tea Party primary challenger Milton Wolf with just 48.1 percent of the vote, Pat Roberts narrowly escaped becoming the first elected U.S. Senator from Kansas to lose a renomination bid in 100 years. The last – and so far only – elected U.S. Senator to lose a Kansas primary was one-term Republican Joseph Bristow in 1914. Bristow was defeated by former U.S. Senator Charles Curtis who went on to win three terms before becoming Herbert Hoover’s running mate in 1928. Only one other U.S. Senator from the Sunflower State has lost a primary since the passage of the 17th Amendment: Sheila Frahm in 1996. Frahm was appointed to fill Bob Dole’s seat earlier that year and finished 13.2 points behind Sam Brownback in the three-candidate primary field. Overall, incumbent senators from Kansas have won 29 times against two defeats in the direct vote era. (Curtis also lost a primary in 1912 to Walter Stubbs, one year before the nation moved to direct elections).