Rep. Lacy Clay, Jr. won the primary fight over St. Louis on Tuesday, emerging without much of a scare from the political Thunderdome of his newly merged district.

Clay defeated neighboring Democratic Rep. Russ Carnahan in a battle between two prominent political family names in the Show Me State.

Clay in 2001 took over the principal St. Louis. City congressional district from his retiring father and Missouri's first African-American representative, Bill Clay, Sr. Carnahan, the son for former governor Mel Carnahan and former senator Jean Carnahan, who filled her late husband's seat when he defeated John Aschcroft posthumously after his death in a plane crash weeks before the 2000 election, has represented South St. Louis and surrounding areas since 2005.

Thanks to redistricting and Missouri's loss of a House seat following the 2010 Census, the two were thrust into a fight for the newly conglomerated district encompassing the heart of St. Louis's metro area, mostly comprised of Clay's present turf.

The campaign saw its a share of racial dynamics and negative campaigning. Clay, who is black, represents predominantly black North St. Louis; Carnahan, who is white, represents predominantly white South St. Louis.

In mailers, Carnahan accused Clay of ties to the rent-to-own industry. On TV, Clay accused Carnahan of voting against Medicare. Both courted black voters with radio ads featuring funk or hip-hop/Afrobeat music. Clay sent "sound trucks" through the city blaring his campaign song, according to a campaign consultant.

In the end, Carnahan wasn't much of a threat: With 99 percent of precincts reporting, Clay led 63 percent to 23 percent.

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