Hollywood’s biggest donors and political influencers had started to sour on President Biden, but Vice President Harris is about to see their sweet side after launching her White House bid.

“There’s new excitement — Hollywood celebrities are lining up behind Kamala as if she were the second coming,” Donald Critchlow, a political history professor and director of Arizona State University’s Center for American Institutions, told ITK.

Following intense pressure from Democratic lawmakers and high-profile figures such as “Ocean’s Eleven” star George Clooney, Biden exited the 2024 race Sunday and endorsed Harris

“I believe it is in the best interest of my party and the country for me to stand down and focus solely on fulfilling my duties as President for the remainder of my term,” Biden, 81, said in a statement.

In the days since, Harris has raked in tens of millions of dollars in fundraising and secured the support of enough Democratic delegates to become the party’s nominee ahead of November.

Some of Biden’s biggest celebrity supporters — including Barbra Streisand, Eva Longoria and “Star Wars” actor Mark Hamill — praised Biden’s move and announced they were backing Harris. 

“I believe in Kamala Harris and believe in our collective effort to organize and win this!” former “Desperate Housewives” star Longoria wrote on social media. 

“I’m so grateful to President Biden and so excited to support Kamala Harris,” Streisand said in a statement to The New York Times.

Hamill called the vice president “the candidate who will both honor and further [Biden’s] legacy,” writing the hashtag “HamillHeartsHarris” on the social platform X

“There may be a different momentum happening now that Kamala Harris has entered the race,” said Mark Harvey, a professor at the University of Saint Mary.

“We now have a younger person who I think is perceived by many as being maybe a little more in touch, maybe a little cooler than ‘old Joe Biden.’ I think that in a way is probably going to attract more celebrities in her direction,” said Harvey, author of “Celebrity Influence: Politics, Persuasion, and Issue-Based Advocacy,” of 59-year-old Harris.

Actor Mark Hamill waves during a stop at a White House press briefing as press secretary Karine Jean-Pierre smiles off to the side.

Actor Mark Hamill, right, joins White House press secretary Karine Jean-Pierre as she speaks with reporters in the James Brady Press Briefing Room at the White House May 3, 2024, in Washington.

Biden previously had a flock of entertainers behind him: Clooney just last month hosted a record-breaking, star-studded campaign fundraiser featuring Julia Roberts and Jimmy Kimmel for the commander in chief before urging him to drop out of the race in a New York Times op-ed published earlier this month. But experts say Harris’s candidacy could reignite Hollywood’s support, both financially and through public opinion. 

“I don’t think they had any choice in endorsing Harris after raising money for Biden and then stabbing him in the back by joining an orchestrated campaign to force him out of the race — so they have to put their money where their mouths are,” said Critchlow, who penned the book, “When Hollywood Was Right: How Movie Moguls, Film Stars, and Big Business Remade American Politics.”

Clooney, in a statement to ITK this week, said, “We’re all so excited to do whatever we can to support Vice President Harris in her historic request.”

According to Harvey, celebrities likely don’t “make a huge difference in terms of electoral outcomes,” but where they can have an impact is when they exercise their immense cash-raising mojo. 

“Where they make a difference is in terms of fundraising, and that’s where [Democrats] may get a differential advantage,” Harvey said. 

But another area where Hollywood could make a difference is in reenergizing young voters.

In the hours after she launched her presidential bid, Harris got a lift from Charli XCX, who dubbed the VP “brat,” a compliment tied to the singer’s latest hit album of the same name.

“I think there’s going to be a cool factor where a lot of these Hollywood people are going to start being a little more public perhaps in the way that they’re expressing themselves,” Harvey said.

But appealing to and getting shoutouts from younger celebrities can only take a candidate so far, Critchlow cautioned, citing the tidal wave of A-list support that former President Obama enjoyed during his White House runs.

“For all the young people’s crusade talk, the youth vote only went up a couple points in his first election bid, and then pretty much fell down [in 2012],” Critchlow said.

“What’s critical to the Democrats is the Midwest, and I don’t think the young Black and white male workers are going to be voting because they have a few young Hollywood celebrities that have endorsed Harris.”

While a smattering of stars have embraced former President Trump’s effort to win back the White House — pro wrestling great Hulk Hogan and “American Bad Ass” singer Kid Rock took to the stage at last week’s Republican National Convention in Milwaukee — Critchlow said there’s an opportunity for the 45th president’s camp to knock Harris’s for appearing to cozy up to left-leaning celebrities.

Trump’s team, he said, could portray the vice president as “part of that elite in Washington and just hang Hollywood around her neck as much as possible.”

Yet, the University of Saint Mary’s Harvey said, “I think that Kamala Harris getting more money is a threat to the Trump campaign.”

Hollywood, like politics, can be unpredictable, and it’s unclear whether the showbiz boost will carry Harris through November. But for now, celeb fervor for Harris’s campaign is similar to an opening-weekend box office smash hit.

“There is a momentum that happens at certain points in campaigns — a measurable point where certain things in the media line up a certain way, and people become energetic, and one or the other candidates sort of has this momentum that kind of pushes and carries them forward,” Harvey said, “and over the last couple of days, Harris has that momentum.”