Georgia Republican Sen. Saxby Chambliss handed the GOP a firewall against Democrats eager to flex their newfound political muscle in Washington, winning a bruising runoff battle Tuesday night that had captured the national limelight.

Chambliss' victory thwarted Democrats' hopes of winning a 60 seat filibuster-proof majority in the Senate. It came after a bitter month long runoff against Democrat Jim Martin that drew political luminaries from both parties to the state and flooded the airwaves with fresh attack ads weeks after campaigns elsewhere had ended.

Minnesota - where a recount is under way - now remains the only unresolved Senate contest in the country. But the stakes there are significantly lower now that Georgia has put a 60-seat Democratic supermajority out of reach.

With 90 percent of the precincts reporting, Chambliss captured 59 percent to Martin's 41 percent. Chambliss' win is a rare bright spot for Republicans in a year where they lost the White House as well as seats in the House and the Senate.

"This is a rare tidbit of good news for a Republican Party reeling from November's losses," said CBSNews.com senior political editor Vaughn Ververs. "While it may seem to have stopped the bleeding, the party remains in the kind of minority status it has not seen since the early 1990s. A runoff victory in a strong Southern state is thin thread upon which to build a political comeback. At the same time, the result is a caution signal to President-elect Obama that his election mandate has its limits."

Martin's campaign said he had called Chambliss to concede and was expected to address some 200 supporters gathered at an Atlanta party shortly.

Chambliss portrayed his win as an encouraging sign for Republicans looking to regroup as they head into the next election cycle.

"I'm excited to be the first race that leads us into the 2010 campaign because it'll be a tough fight," Chambliss said at a victory party in Cobb County.