PARMA, Ohio (Reuters) - Rock star Bruce Springsteen and political star Bill Clinton teamed up on behalf of President Barack Obama on Thursday, hoping to drum up support in a state crucial to the Democrat's re-election hopes.

Springsteen sang songs about working-class struggles and cited Obama's work in his first term while former president Clinton took a swipe at Republican candidate Mitt Romney's economic plans.

Echoing a frequent talking point of the Democrats, Clinton told 3,000 supporters at a community college that Obama had saved jobs in Ohio when he bailed out the auto industry based in neighboring Michigan in 2009.

""When you were down, you were out and your whole economy was threatened, the president had your back. You've got to have his back now," Clinton said.

Besides whipping up support for Obama, Springsteen paid tribute to Clinton, who had taken the stage before him.

"It's like I am going on after Elvis," said the 63-year-old New Jersey musician, who talked about his working-class roots and played an acoustic set with guitar and harmonica.

"I remember President Obama's election night. It was an evening when you could feel the locked doors of the past finally being blown open," Springsteen said. "Then comes the hard daily struggle to make those possibilities real in a world that is brutally resistant to change."

Springsteen campaigned for Obama in 2008 and Thursday's appearance was his first for Obama this year. On Wednesday he posted an open letter on his website explaining why he supports Obama.

Ohio is a crucial battleground where Obama has a narrow lead in polls of 2.4 percentage points, according to poll aggregator RealClearPolitics heading into the November 6 election.

SONG ABOUT HARD TIME IN OHIO

Springsteen played some of his hits such as "The Promised Land," "No Surrender," the Woody Guthrie standard "This Land Is Your Land" and "We Take Care of Our Own." He also sang a light-hearted campaign song based on Obama's "Forward" theme.

In a nod to local economic struggles, Springsteen gave a rendition of "Youngstown" from his 1995 album. The song's message of hardship in an Ohio steel town went well with Obama's message that he understands blue-collar workers trying to rebuild the economy after years of war and hardship.

Obama won Ohio by a little more than 200,000 votes in 2008. His campaign, which frequently plays Springsteen tunes at events, is concerned Ohio could be even closer in 2012.

Republicans have often ridiculed Obama for his friendships with Hollywood stars. They dismissed the Springsteen and Clinton event.

"Obama has had a litany of stars perform on his behalf and it really hasn't move the numbers," said Republican strategist Ron Bonjean. "If Bruce Springsteen could change the unemployment figure that would be a whole other story."

Clinton jabbed at Romney, who founded a private equity firm, saying he championed economic policies that benefit the wealthy at the expense of the poor and middle class and for not providing greater transparency on his personal taxes and budget proposals.

"Where are your numbers? This guy ran Bain Capital and is a business guy and he is hiding his budget? That ought to tell you something," Clinton said.

Obama could do with the help after losing a lead in polls nationally, as well as in some swing states, following his poor debate performance on October 3.

Early voting has begun in Ohio and both parties are working to get voters to cast early ballots.

More than 400,000 Ohio voters have already cast ballots out of some 7.9 million registered to vote, according to elections officials' latest data. Most have been from Cuyahoga County, the site of Thursday's rally.