WASHINGTON (AP) — The Republican infighting over Florida’s Senate seat that drove Gov. Charlie Crist to ditch the GOP is giving an underdog Democrat a realistic shot at pulling off an upset in the fall.

Democratic Rep. Kendrick Meek, who appeared headed to a lopsided loss in November, suddenly looks like a plausible contender to snatch away victory as Crist’s decision to run as an independent sets up a three-way race that could split Republicans between the governor and Republican favorite Marco Rubio.

Democrats welcomed Crist’s announcement as the fallout from a “corrosive civil war” in the Republican Party. Meek, a 43-year-old congressman from Miami and a former state trooper, said his campaign is in a “commanding position” and offers voters a clear alternative to two “bickering” Republicans.

“The governor and Marco Rubio have spent hundreds of thousands of dollars talking about back-waxing and things of that nature,” Meek said, referring to barbs that Crist and Rubio traded recently, including Crist’s suggestion that Rubio used Republican Party funds to have his back waxed. “We haven’t even taken a 15-second ad on radio.”

Meek, who is heavily favored to take the Democratic primary in August, could win the general election with just over a third of the vote, instead of the 50 percent-plus majority he would have needed in a head-to-head matchup against Crist or Rubio. Meek would be Florida’s first black senator and the first black senator from the South since Reconstruction.

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“I think it’s a jump ball,” said Steve Schale, a Democratic consultant who ran President Barack Obama’s Florida campaign in 2008. “Meek probably did have an uphill battle in a two-way race … but now people are looking at it and saying, ‘Wait, this is doable.’ You’re already seeing some of the institutional supporters of the Democratic Party getting excited.”

Meek must first get past a handful of lesser-known candidates in the Democratic primary — a race that got more crowded Friday as billionaire Jeff Greene announced his candidacy. Greene, a real estate investor who has rubbed elbows with some well-known names — boxer Mike Tyson was his best man — could spend heavily.

The shifted dynamic in the nation’s largest swing state is a rare point of hope for Democrats in an otherwise gloomy electoral climate in which the party is expected to see significant erosion of its congressional majorities.

The mood was far different in January 2009 when Meek decided to risk his promising congressional career by running for the Senate. Just a few months earlier, Obama had won Florida with 51 percent of the vote and Republicans were searching for an identity. Meek, who has had a charmed political career after winning his first election to the state House at age 27 and handily winning four congressional terms, hoped to ride a wave of Democratic momentum into the Senate.

But a sour economy and outrage over government bailouts quickly changed that, creating an anti-incumbent fervor so strong that even Crist, a previously popular Republican governor, was essentially chased out of the GOP primary in favor of the upstart conservative Rubio.

The climate did not bode well for Meek, who followed his mother, Carrie Meek, the granddaughter of a slave, into Congress. Polls showed him as a significant underdog, unable to break 40 percent against either Crist or Rubio in a recent Quinnipiac University survey.

While Crist’s defection doesn’t make Meek a favorite, it makes his task much easier: He might not need 40 percent to win. And with 42 percent of Florida’s 11 million voters registered as Democrats versus 36 percent Republicans, he can focus mostly on securing his political base instead of trying to forge a broader coalition with independents, as Obama had to do.

Building such a coalition was proving challenging for Meek. The Democrat, who socially seems just as comfortable mingling with liberal colleagues in the Congressional Black Caucus as he does with conservative Republicans, has been a party loyalist throughout his career. He voted for the party’s health care bill and the $787 billion economic stimulus package and consistently votes with party leaders.

Meek has tried to cast himself as a moderate in the campaign — the cigar-loving lawmaker hunts and fishes — but now his Democratic record may play to his advantage. With Rubio shoring up the conservative vote, Meek’s biggest challenge may be fending off a strong run by Crist to win over Democrats.

Republicans, in fact, are arguing that Crist’s switch could hurt Meek more than it will help.

“I think Charlie Crist is a more powerful draw for Democratic votes than Kendrick Meek,” said Rep. Adam Putnam, R-Fla. “Crist will definitely pull more Democratic votes than Republican votes.”

Meek, who is little known outside his south Florida district, also could face financial hurdles in boosting his name recognition in a large state with expensive television markets. He has $3.7 million in his campaign bank, in line with Rubio’s $3.9 million but far less than Crist’s $7.6 million.

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