Donald Trump is a con man, and if you support him for president, you are his latest mark.

Commentators have been warning voters of this obvious scam for months. Trump's latest campaign filing makes it clear. The man is unwilling or unable to do what it takes to win a general election, and a huge portion of the money he does raise flows straight into the companies he owns.

"It's very possible," Trump said in 2000, "that I could be the first presidential candidate to run and make money on it."

Donald J. Trump for President, Inc., filed its monthly report on June 20, documenting its receipts and disbursements for May, the month in which Trump sealed the Republican nomination and supposedly began the general election.

Trump's campaign raised $5.6 million in May. Mitt Romney raised more than twice that in May 2012. Hillary Clinton raised five times as much — $28 million — in that same period.

Trump's campaign entered June with $1.3 million on hand — a shockingly low number. Hillary had $42 million on hand. Romney had $9.2 million on hand.

Trump's campaign spent $6.7 million in May — more than it raised. And a lot of that money was spent on, well, Donald Trump.

As the Huffington Post's Christina Wilkie reported Tuesday morning, Trump's campaign spent more than $1 million of that money on Trump companies' products and services last month, "for facilities rental, catering, monthly rents and utilities at more than a half-dozen Trump-owned companies and properties." The amount "includes nearly $350,000 that the Trump campaign paid a Trump-owned company, TAG Air, for the use of Trump's private jets and helicopters."

The Associated Press found that Trump's campaign has spent $6 million since it began at Trump businesses.

Trump Cafe, the lunch spot in Trump Towers which sells the salad bowls Trump appeared with in a Cinco de Mayo tweet proclaiming "I Love Hispanics!" has pocketed $94.61 from the campaign over the past year, according to an analysis by journalist Derek Willis. (Trump's filings show that Trump campaign staffer Megan Powers expensed $25 at Trump Towers on May 5. Trump Cafe sells its taco bowls for $18.)

More than a dozen other Trump entities received a lot more from Trump's campaign.

Trump SoHo, a hotel near NYU, has received $100 from Trump's campaign.

Trump for President has paid about $400 to Trump Ice, LLC, which doesn't sell ice, but sells bottles of water (which, to be fair, can be turned into ice fairly easily).

Trump's Las Vegas, New York, and Chicago Hotels all pocketed Trump for President cash.

Trump's Mar a Lago Club, where he lives, also made tens of thousands off the Trump campaign.

To understand what's going on here, some understanding of Federal Election Commission law is necessary.

Trump the businessman cannot legally let Trump the candidate use Trump properties for free. The FEC wouldn't want Marriott Corporation making giant, hidden, in-kind donations to politicians by giving their campaigns free rooms, and so the campaigns are required to pay market rate.

What's true for Marriott is true for Trump Hotels. If Trump campaign staff wants to stay at Trump Hotels, the campaign staff has to pay full rate. But here's the thing: The Trump International Hotel & Tower, where the Trump campaign spent more than $10,000 on lodging in March and April, is the most expensive hotel in the neighborhood.

In typical Trumpian style, the standard room there is called the "Deluxe Room," and it costs $300 a night. The Intercontinental around the corner is less than half that. The Renaissance Chicago Downtown, just across the river, is about $100 cheaper.

If Trump's campaign could save money by staying at Trump's hotels, that might be a shrewd move. But legally, they can't, which means staying at Trump hotels is more costly to the campaign and a lot more profitable to Trump.

A final detail: Trump's campaign is $45.7 million in debt (which, you may note, is a lot more than its $1.3 million cash on hand). And all of that debt is owed to ... Donald J. Trump.

That means that every penny of the next $45.7 million in donations to the Trump campaign could literally go directly to Trump's personal bank accounts before this is all over.

Trump has said he's funding his own campaign. If he were really doing that, he would forgive his campaign's debt to Trump, thus freeing up future campaign contributions for the actual campaign. But does that seem like something Trump would do?

Timothy P. Carney, the Washington Examiner's senior political columnist, can be contacted at tcarney@washingtonexaminer.com. His column appears Tuesday and Thursday nights on washingtonexaminer.com.