Many Hollywood heavyweights who had supported Hillary Clinton are rallying behind Barack Obama, pledging money and star power to his U.S. presidential bid before a big fundraiser next week.

Experts say that since Clinton conceded defeat this month after a grueling Democratic nominating contest, celebrities have quickly united behind Obama.

The result, they said, could be a campaign cash windfall for the senator from Illinois, but star support doesn’t necessarily translate directly to votes.

Sherry Bebitch Jeffe, a senior scholar at the University of Southern California, said that once a politician becomes known, voters look for candidates with positions they like and with whom they can identify, regardless of celebrity backing.

In fact, stars can cause harm if a performer’s public image rubs voters the wrong way. That happened when Jane Fonda and Barbra Streisand campaigned for former Texas Gov. Ann Richards in her conservative state, and Richards lost the bid.

“Sometimes they can come back to bite the candidate,” Jeffe said.

But Los Angeles is a town where stars wield a great deal of power and have money to spend, and numerous celebrities are expected to turn out at a Tuesday fundraiser featuring the singer Seal — at a cost of $2,300 per ticket.

Director Steven Spielberg and his partner in the Dreamworks movie studio, David Geffen, and Dreamworks Animation Chief Executive Officer Jeffrey Katzenberg are organizing another Obama fundraiser later this year, said Andy Spahn, a consultant to the Hollywood power trio.

“If a Hollywood celebrity puts his or her mind to it, they’re good money raisers,” Jeffe said.

ALIGNING THE STARS

Mitchell Schwartz, who was Obama’s California campaign manager through the primary election season, said Obama’s appeal in Hollywood had been limited, until now.

“I don’t think we were the Hollywood candidate — ever,” Schwartz said. “I think Hillary might have been more … she might have had more support.”

Other Obama celebrity endorsers include actors talk show host Oprah Winfrey and actors Robert De Niro, Tom Hanks, Scarlett Johansson and Halle Berry.

Billionaire Geffen upset many Hollywood power players last year when the longtime Clinton supporter broke for Obama.

Oscar winner Hanks, the star of “The Da Vinci Code,” gave money to Bill Clinton’s legal defense fund when he was president, but endorsed Obama with an online video in early May, when Hillary Clinton was still campaigning.

During the primaries, Obama had trouble attracting Hispanic voters in some states because, analysts said, some Hispanics were reluctant to vote for a black candidate.

But a pro-Obama video in Spanish with Hispanic actors Jessica Alba of “The Love Guru,” John Leguizamo of “The Happening” and comedian George Lopez, has attracted more than 250,000 viewers on the video sharing site YouTube.com.

“It helps build a broader sense of a candidate’s support,” said professor Chon Noriega, director of the University of California, Los Angeles, Chicano Studies Research Center. “But I don’t think that because George Lopez said support (a candidate) somebody’s going to say, ‘Well that’s who I’m going to vote for.”‘

Presumptive Republican candidate Sen. John McCain also has his celebrity endorsers, including actors Robert Duvall and Sylvester Stallone.

Reuters/Nielsen