As top Republicans expressed astonishment and alarm over Donald Trump’s meager campaign fundraising totals, the presumptive nominee blamed party leaders Tuesday and threatened to rely on his personal fortune instead of helping the party seek the cash it needs.

New campaign finance reports showing that Trump had less than $1.3 million in the bank heading into June ignited fears that the party will not be able to afford the kind of national field effort that the entire Republican ticket depends on.

GOP fundraisers have failed to rally around his campaign

The real estate mogul said party fundraisers have failed to rally around his campaign.

“I’m having more difficulty, frankly, with some of the people in the party,” Trump said on NBC’s “Today,” adding, “They don’t want to come on.”

“If it gets to a point,” he said, “what I’ll do is just do what I did in the primaries,” when he lent his presidential campaign more than $43 million.

The billionaire developer increased his line of credit to the campaign by an additional $2.2 million last month – the smallest amount he has shelled out this year – but Trump said in a statement Tuesday that “if need be, there could be unlimited cash on hand as I would put up my own money.”

It’s unclear how quickly he could access the hundreds of millions needed to finance a national campaign. In May, he suggested he’d have to “sell a couple of buildings” to do so.

If he did tap his wealth to finance his bid, it would effectively amount to abandoning the Republican National Committee and the rest of the ticket, which relies on the presidential nominee to help fund a national field organization.

Republican strategist and fundraiser Austin Barbour said that if Trump’s fundraising does not pick up, it “could have a devastating impact” on the party.

“If they don’t fix this in a massive way, it’s going to have widespread implications down the ballot. It just is,” Barbour said. “If he’s not raising hundreds of millions of dollars, there are gubernatorial races, Senate races, congressional races, attorney general races, you name it, that will be impacted. Those races are dependent upon get-out-the-vote efforts from the RNC and the presidential campaign.”

TRUMP: FUNDRAISING ‘INCREDIBLE’

The Trump campaign released a statement touting its fundraising as “incredible” since the candidate held his first finance event May 25. Its joint fundraising committee with the RNC is expected to bring in at least $20 million in June, with $6 million coming from a pricey dinner in New York on Tuesday night, according to a person familiar with the figures.

The vast share of the money will go to the national party committee. Republican officials said the party already has nearly 500 field staffers deployed around the country and noted that the RNC has outraised its Democratic counterpart by $46 million during this cycle.

But top Republicans said Trump squandered May by neglecting to capitalize on clinching the nomination to build a grass-roots fundraising base.

There is also growing scrutiny of his use of his companies as vendors. Of the $63 million his campaign spent through May, more than $6 million went to pay Trump properties or reimburse Trump and his family for costs, according to an analysis by The Washington Post.

The Trump campaign did not respond to questions about the payments.

Meanwhile, expected Democratic nominee Hillary Clinton has been stockpiling cash. She raised more than $28 million in May and started June with $42 million in the bank.

Trump is “now looking into the abyss,” said Ed Rollins, the top strategist for Great America PAC, a pro-Trump super PAC. “He can either start writing checks and selling some buildings and golf courses or get on the phones and talk to donors. Big donors just don’t want to give money unless they have the opportunity to talk to the candidate, hear what your positions are. There’s just been a failure from start to finish on the fundraising side.”

NO CALLS TO BIG DONORS

Among those who had yet to receive a call was Fred Malek, the well-connected finance chairman of the Republican Governors Association.

“Many leading donors are waiting to see him take a more inclusive, tolerant and substantive approach to campaigning,” Malek said. “Even if they all came around with great enthusiasm, there’s no way in this short time frame … he can build the kind of organization that will be competitive financially. Hillary Clinton’s been at this for several decades.”

The problems have spilled over to the RNC, which took on $2 million in added debt in May, underscoring how Trump’s failure to build a fundraising structure has put financial pressure on the national party committee.

“Trump’s fundraising is shockingly thin and has created a dark cloud over his ability to be financially competitive with the Clinton machine,” said Scott Reed, a veteran Republican operative and top strategist for the U.S. Chamber of Commerce. “While the finance numbers are weak, this is nothing a smart VP choice, an exciting, substantive convention and a strong first debate performance cannot overcome.”

Other Republican financiers were more pessimistic. Trump has resisted making fundraising calls to major donors and is uncomfortable soliciting support because he is so accustomed to being wooed himself, according to people familiar with the situation. Some of the party’s most reliable bundlers have declined to sign on to the fundraising operation. And the campaign’s staff has also been slow to schedule finance events around the country.

Republican strategists were particularly exasperated that Trump has been slow to tap into his fervent base of supporters for small donations online, potentially leaving tens of millions of dollars on the table.

Trump on Tuesday sent what he touted as his first fundraising email. (It wasn’t: A joint fundraising committee he has with the RNC sent a solicitation in his name on June 8.)

“I’m going to help make it the most successful introductory fundraising email in modern political history by personally matching every dollar that comes in WITHIN THE NEXT 48 HOURS, up to $2 million!” Trump wrote.

It was unclear whether he means to actually donate funds or continue to loan cash to his campaign. The billionaire has now lent his campaign $45.7 million and given it $400,000 more, while collecting $17 million in contributions.

In May 2012, the national party scooped up more than $34 million, ending the month with more than $60 million in the bank and $9.9 million of debt. Nearly $26 million that month came through Romney Victory, a joint fundraising effort between the party and the 2012 nominee, Mitt Romney.