Donald Trump on Tuesday made his first formal pitch to potential campaign donors, saying in an e-mail that, “I need your help . . . to beat Crooked Hillary” — but also boasting that he could pick up the tab himself if it came to that.

“This is the first fund-raising e-mail I have ever sent on behalf of my campaign. That’s right. THE FIRST ONE,” the presumptive GOP nominee said in the e-mail, sent the morning after Federal Election Commission records showed that his campaign began June with $1.3 million in the bank compared to $42 million in Hillary Clinton’s coffers.

Trump also offered to match up to $2 million in donations to “help make history.”

But in another e-mail, the billionaire real-estate developer declared that he would fund the entire campaign alone if he had to.

“If need be, there could be unlimited ‘cash on hand,’ as I would put up my own money, as I have already done through the primaries, spending over $50 million dollars,” Trump wrote.

Analysts said the former reality-show star probably could foot the entire bill — despite lingering questions over just how wealthy he really is.

“The easiest answer is for Donald Trump to offer up a substantial sum of money each month for the next four months and encourage his supporters to match him,” GOP strategist Karl Rove told The Post.

Ari Fleischer, onetime spokesman for ex-President George W. Bush, brushed criticism aside.

“If you measure him by conventional norms, it’s a massive failure,” Fleischer said. “But he does everything differently. And by the stroke of a pen, none of this matters.”

Veteran GOP consultant Charlie Black said Trump’s fund-raising should take off now that he’s becoming partners with the Republican National Committee and did not see his current war chest as a major drawback.

“Especially not if he says he’s the backup to cover the budget,” Black told The Post.

During a TV interview earlier on Tuesday, Trump knocked the GOP for not doing more to help his campaign.

“I’m having more difficulty with some people in the party than I have with the Democrats,” he said on NBC.

But the RNC nonetheless came to Trump’s defense, as his fundraising was mocked by Democrats and was trending on Twitter under the hashtag #TrumpSoPoor.

“Donald Trump financed his campaign all the way to this point by adding in more of his own personal money,” RNC spokesman Sean Spicer told CNN. “So it’s false to say that he has $1.3 million.

If he wanted to get that number up in two seconds, he just strokes a check and it’s up.”