Republican Allen West narrowly leads U.S. Rep. Ron Klein in a bruising battle for South Florida’s 22nd Congressional District, a new Sunshine State News Poll shows.

West leads Klein 47-44 in the survey of likely voters conducted Oct. 17-19. Nine percent of respondents are undecided.

West, a retired Army lieutenant colonel, lost by 10 points to Klein in 2008, a strong year for Democrats. But with Republicans surging this fall, West is picking up more independents, along with solid tea party support.

“West has to be the slight favorite here simply because of the turnout differential,” said Jim Lee, president of Voter Survey Service, which conducted the poll for Sunshine State News.

Lee reported that West’s 3-point lead grows to 5 points among respondents who say their chances of voting are “excellent” (49-44) and 4 points among “2x” voters, or those who cast ballots in both the ’08 and ’06 general elections (48-44).

Both candidates are feeling the effects of harsh, negative advertising in the closely fought race. Klein has a 39/43 favorable/unfavorable rating while West has an almost identical 40/43 split.

The poll shows a polarized district, with West winning Republicans 78-14, and Klein winning Democrats by a nearly identical 78-13 margin.

“Clearly, this race will be a referendum on the president,” Lee said. “Voters who approve of the job Obama is doing are voting for Klein 87-7, while those who disapprove of the president are voting for West 84-8.

“Since Obama’s overall job approval is inverted 52-43, we’d give the edge to West because the enthusiasm favors the GOP this year.”

Still, Lee said the poll numbers do not rule out a Klein victory.

“Given how close this district is in voter registration, if Klein turns out a larger share of his base than West. he could still eek this out,” Lee said.

Klein, a two-term congressman, has blanketed the airwaves with attack ads highlighting West’s alleged personal financial problems and plastered pictures of West hanging out with a leather-clad motorcycle group.

West fired back, calling Klein a “mama’s boy” for House Speaker Nancy Pelosi. The campaign told Sunshine State News it will distribute pictures of the congressman consorting with the same bikers Klein brands “gangsters, thugs and criminals.”

“In actuality, they’re Vietnam veterans,” said West spokesman Josh Grodin.

“Frankly, Klein doesn’t have a message. He’s just running from his record and attacking Allen West,” Grodin said.

“We’re not surprised by this poll,” he added. “Our internal tracking shows similar numbers.”

The Klein campaign did not respond to Sunshine State News’ requests for comment.

In the race for campaign cash, West is also leading, according to Sept. 30 filings with the Federal Election Commission.

West had collected $5,167,340, with $1,629,395 cash on hand. In the past quarter, the Republican raised $1.6 million — quadruple the amount he received during his entire 2008 campaign.

“Ninety-nine percent is coming from individual contributions, with an average donation of $75,” Grodin noted.

Klein’s report showed total collections of $3,155,349, with just $270,499 cash on hand.

Rick Wilson, a Republican campaign consultant, called the Klein-West contest “one of the biggest stories” of this political season.

“Ron Klein was just sitting back expecting to be re-elected to another term and West has overachieved,” Wilson said.

CD 22, which stretches from Fort Lauderdale to Jupiter, leans Democratic in presidential election years, but tends to be more of a tossup during midterm elections when turnouts are lower. Republican Rep. Clay Shaw represented the district for 26 years before he was ousted by Klein in 2006.

The Sunshine State News Poll, which surveyed 800 voters, has a margin of error of +/- 3.46 percent.