Billionaires from coast to coast are putting their influence and money behind Donald Trump, a wave of support that is helping the former president narrow his fundraising gap with President Joe Biden and seize new momentum in his race for the White House.

Some have already donated millions to his campaign, some have announced plans to do so, and some are only saying for now that they will vote for him.

Trump, meanwhile, is returning the favor.

He is reportedly promising to make policy changes that would help their businesses and perhaps even rely on them as advisers if he returns to the White House. The Wall Street Journal reported Wednesday that Trump and Tesla (TSLA) CEO Elon Musk have discussed a formal advisory role for the billionaire if Trump should win.

The close back-and-forth with billionaires is a notable departure from Trump’s previous Oval Office runs that often focused more on smaller contributors. The website OpenSecrets tracks donations by size and found that "large contributions" made up about 14% of Trump’s bankroll in 2016. That same figure this time around is more than 68%.

The latest example of elite support came last week with the news that Blackstone (BX) CEO Steve Schwarzman, after years of keeping his distance from Trump, is now a supporter.

The financier told Axios he's supporting Trump and will donate to him as a "vote for change."

He is just the latest wealthy donor to overcome past objections to Trump's conduct and character. Schwarzman responded to the events of Jan. 6, 2021, by saying at the time that the "insurrection that followed the president's remarks today is appalling."

Traditional GOP megadonors return to Trump

The flip in GOP donor support to Trump comes after many billionaires tried to boost his Republican rivals, especially Florida Gov. Ron DeSantis and former UN Ambassador Nikki Haley.

But that quickly changed after the primary season ended.

Haley ended her run in March and Trump then outraised Biden in April. That was largely due to a single event featuring an assortment of billionaires at hedge fund manager John Paulson's home in Palm Beach, Fla.

The event raised more than $50 million in a single night.

In total, Trump raised about $76 million in April, besting Biden's $51 million. But Biden is still ahead when it comes to cash in the bank, with $192 million saved across his operation.

A collection of familiar GOP names announced their support for Trump in recent months, in addition to Schwarzman. They include figures like hotel tycoon Robert Bigelow and activist investor Nelson Peltz.

Both have donated to Republicans for years. Both distanced themselves from Trump after Jan. 6. Both are now back on board.

Robert Bigelow, the billionaire owner of Budget Suites of America and founder of Bigelow Aerospace, previously backed DeSantis, but he has since made plans to give over $20 million to Trump.

He also reportedly co-chaired the recent fundraiser at Paulson's Florida home.

For his part, Peltz told the FT earlier this month he would vote for Trump, but donations may or may not be forthcoming. "I'm not happy about that," he told the paper, saying he still had misgivings about Trump but that they were outweighed by his concerns about Biden's fitness for office.

Peltz — who recently lost a high-profile proxy battle with Disney (DIS) and its CEO Bob Iger — donated to Sen. Tim Scott during the presidential primary season.

Peltz supported Trump financially and with his vote in 2020 but said on CNBC on Jan. 7, 2021, he was "sorry I did that."

Some traditional GOP megadonors are still holding out, at least for now.

Billionaire hedge-fund investor Kenneth Griffin told attendees at the Qatar Economic Forum earlier this month that he wants to see who Trump picks as his running mate first.

Peter Thiel, the co-founder of PayPal who has long bankrolled GOP campaigns, told the Atlantic late last year he wouldn't be giving any money to Trump or anyone else during this presidential campaign.

Outreach to oil executives

Trump has also received support from wealthy energy executives after what appears to be a concerted outreach effort to that industry.

Trump has reportedly made direct appeals for donations in return for looser restrictions on things like oil drilling if he wins.

That outreach may have pushed the limits of campaign finance laws, according to the Washington Post, with Senate Democrats promising to investigate.

Trump and the industry are "conferring on how to trade campaign cash for policy changes," said Sens. Sheldon Whitehouse and Ron Wyden in a recent statement. "Such potential abuses must be scrutinized."

But the promises appear to have allowed Trump inroads with oil executives.

Harold Hamm, the founder and chairman of oil and natural gas company Continental Resources, has increased his alliance with Trump in recent months.

Federal Election Commission (FEC) data shows a contribution of $614,000 from Hamm to Trump's joint fundraising committee at the end of March.

Hamm had a relationship with Trump that stretched back for years, but he distanced himself after 2020 and gave money to Haley as recently as last year.

A beachhead of support in Silicon Valley

Perhaps the most surprising source of potential billionaire support for Trump comes in traditionally deep-blue Silicon Valley.

Multiple recent reports from The New York Times to Puck have chronicled ongoing efforts from venture capitalist David Sacks and Chamath Palihapitiya of Social Capital to organize a fundraiser on Mr. Trump's behalf.

Whether the fundraiser — and a possible appearance on the pair's podcast—eventually comes together remains to be seen. But the news was especially notable given the long history the two men have of donating to Democrats.

Palihapitiya gave Biden more than $250,000 during the 2020 campaign, according to FEC data.

Other prominent figures like Marc Andreessen of Andreessen Horowitz and Shaun Maguire, a partner at Sequoia Capital, have lambasted Biden on their social media feeds but, as of yet, have declined to get behind Trump.

Another closely watched figure is Musk. The current third-richest man in the world has unleashed an onslaught of anti-Biden commentary online this year and says he can't imagine voting for Biden this fall.

The trend comes after years of Musk's deepening ties with Republicans. A new Wall Street Journal report this week demonstrated the increasingly warm relationship between Trump and Musk after Musk posted in 2022 that Trump should "hang up his hat & sail into the sunset."

Musk met with Trump in March and, according to the report, now talks with Trump several times a month. The two men have even reportedly discussed giving Musk a formal advisory role on border security, an issue Musk is keenly focused on, as well as on the economy.

What remains to be seen is whether Musk stays true to a promise he made in March when he posted, "I am not donating money to either candidate for US President."

Ben Werschkul is Washington correspondent for Yahoo Finance.

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