-- After a long night of vote-counting -- and a much longer runoff battle -- the Associated Press has named David Perdue the winner of Georgia's Republican Senate primary.
With all precincts reporting, the former Dollar General CEO and cousin of former Gov. Sonny Perdue led with 50.9 percent of the vote to Rep. Jack Kingston's 49.1 percent.
A recount is still technically possible if Perdue's advantage dips below one percentage point after the casting of already-filled-out provisional ballots, which Georgia voters can do until Friday. But if the results hold, Perdue will run against Democrat Michelle Nunn in the November general election.
Perdue's win sets the stage for a competitive general election against Nunn, the daughter of former Georgia Democratic Sen. Sam Nunn, who registered a narrow lead over Perdue when the Atlanta Journal-Constitution polled Georgians in May. Democrats have not won a statewide race in Georgia since 2000.
Perdue overcame Kingston after an overwhelmingly negative and protracted primary. His win was a defeat for the heavy-spending U.S. Chamber of Commerce, which dropped at least $2.3 million into Georgia to support Kingston, according to disclosures to the Federal Election Commission.
As the top two finishers in Georgia's seven-candidate May 20 primary, Perdue and Kingston were campaigning for Tuesday's runoff for the last two months. They saturated Georgia's airwaves, seeking to link each other to support for "amnesty" for immigrants who came to the country illegally and to paint the other as fiscally liberal.
Perdue, who was backed by former presidential candidate Herman Cain, attacked Kingston's long career in Washington, D.C., in a series of TV ads -- the congressman has served in the House since 1993 -- and his record of earmarking, which has placed Kingston near the top of Congress in sponsoring or cosponsoring federal earmarks at times during his tenure.
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Kingston emerged as a consensus candidate among tea-party and establishment endorsers, having won the support of the U.S. Chamber of Commerce, former primary foe Karen Handel (the Sarah-Palin-endorsed tea partier in the race), conservative blogger Erick Erickson, and the National Rifle Association.
Kingston attacked Perdue's business career in a series of ads tweaked by fact-checkers, pointing to layoffs, a government-agency bailout, offshoring, and support for a comprehensive immigration-reform bill among the companies and industry boards with which Perdue was involved.
Despite the bitter and protracted, down-to-the-wire primary, Kingston and Perdue were almost certain to unite against Nunn, who was already facing an attack ad from a GOP super PAC. The two men have pledged to support each other against Nunn after their primary concludes.