(Reuters) - President Joe Biden will attend a glitzy fundraiser in Los Angeles on Saturday with top Hollywood celebrities and former President Barack Obama, amid Democratic anxiety over opponent Donald Trump's growing fundraising clout.

Late-night TV host Jimmy Kimmel will interview Biden and Obama and Hollywood celebrities George Clooney and Julia Roberts are guests, in the latest star-studded event Biden's campaign hopes shows strength and momentum despite Biden's low approval ratings and concerns about his age.

The Biden campaign is hoping to repeat the buzz it generated with a March event in New York City where Stephen Colbert hosted Biden, Obama and Bill Clinton for an event that raised $26 million. The top-ticket package for the LA event costs $500,000, campaign officials said.

"This will be one of the biggest fundraisers we've had," said Ajay Jain Bhutoria, deputy finance chair at the Democratic National Committee. "We are expecting an unprecedented turnout from the enterntainment industry," he said.

In recent weeks, Mark Hamill of Star Wars fame made a White House briefing room appearance to praise the president, Robert DeNiro showed up in lower Manhattan for a press conference at the Biden campaign's behest and Steven Spielberg has been helping the Biden campign with storytelling.

Actor Michael Douglas held a fundraiser for the president and artists Queen Latifah, Lenny Kravitz, Lizzo, James Taylor, Christina Aguilera and Barbra Streisand have all performed to help Biden raise money.

A top campaign source said the fundraising at Saturday's event in Los Angeles is expected to be lower than New York. The source did not share additional details. The Biden campaign did not comment on funds they expected to raise from the event.

Biden campaign's fundraising in April lagged Trump's for the first time, after the former president ramped up his joint operation with the Republican National Committee and headlined high-dollar fundraisers.

Democrats still maintained an overall cash advantage over Trump and the Biden campaign continues to have a considerably larger war chest.

Biden and Trump are tied in national polls with less than five months to go before the Nov. 5 election, while Trump has the edge in the battleground states that will decide the election, recent polls show. On economic issues like inflation, Trump scores higher with voters overall than Biden.

Democrats have long counted on the liberal Los Angeles area as a rich source of financial backing. Republicans often decry Democrats nationwide as funded by Hollywood elites and California liberals.

But the state's donors bankroll presidential campaigns on both sides of the aisle. Biden and Trump have both raised more in the state for their reelection bids than anywhere else, according to fundraising disclosures filed with the Federal Election Commission.

Biden raised $24 million through April 30 in California, and Trump $11.7 million, according to the Federal Election Commission.

The president was largely unable to host high-dollar Hollywood fundraisers for much of 2023 because of industry strikes. But since they were resolved, Biden has headlined several fundraisers in the state, including one in December where top tickets approached $1 million.

(Reporting by Nandita Bose in Washington; Editing by Heather Timmons and Alistair Bell)

By Nandita Bose