William Lacy Clay Jr. defeated Russ Carnahan on Tuesday in a congressional primary caused by the once-a-decade redrawing of the state's political boundaries.
The three-candidate Democratic primary in Missouri's 1st Congressional District pitted two long-time incumbents in a St. Louis district crafted by Missouri's Republican-led legislature when the state lost one of its nine congressional districts after the 2010 Census. Candice Britton, never considered a threat to the established Democrats, finished third.
Both men are members of prominent Missouri political families. William Lacy Clay Sr. represented St. Louis in the House for 32 years before his son took office after the 2000 election.
Carnahan's grandfather served in Congress and his father was governor of Missouri before dying in a 2000 plane crash. Russ Carnahan first won election to the U.S. House of Representatives in 2004. His younger sister, Robin Carnahan, is Missouri's secretary of state.
Six other members of Congress from Missouri were also on Tuesday's primary ballot. Two ran unopposed and the other four were considered strong favorites.
Carnahan chose to face Clay rather than seek an open seat in the 2nd District created after Rep. Todd Akin decided to run in the Republican primary for U.S. Senate. Former state Republican Party Chairwoman Ann Wagner is the front-runner to replace Akin in the Republican-leaning district. She faced three challengers in the GOP primary.
The two men's parallel paths have given way to a pugnacious - if not bitter - primary contest magnified by the election's racial implications. Carnahan is white and Clay black, with the newly drawn district containing a majority of racial minorities. A Clay loss would have left St. Louis without a black member of Congress for the first time in more than four decades.