If celebrity mogul Donald Trump has enjoyed favorable early poll ratings and a burst of media coverage, his personal fortune gets the credit. Without his vast wealth, the bombastic, flamboyant Trump would be dismissed out of hand.

But Trump’s money will hurt him more than it helps if he runs for the White House. Trump’s actual worth is hotly disputed, and it’s not clear how much money he actually controls. His erratic business dealings are coming in for some harsh scrutiny. Most importantly, self-financed candidates have a history of self destructing.

Trump’s company is “much bigger and much more powerful and much stronger than anyone really knows,” he told CNN’s State of the Union this month, declaring that he has a “much, much bigger net worth” than ex-Massachusetts governor and businessman Mitt Romney. Fortune magazine has pegged Trump’s net worth at $2.7 billion.

“Trump has enough to make him credible, particularly in the so-called money primary season,” said Sherry Bebitch Jeffe, a political scientist at the University of Southern California. But Jeffe added that numerous questions dog Trump’s international empire of golf courses, casinos, hotels, and condos, which include two failed real estate developments in Florida and Mexico.

“How much is liquid, for one thing? He’s very vested in lands and properties,” noted Jeffe. “And how much of that is he willing to spend?”

Estimates of Trump’s value, including those made by The Donald himself, range anywhere from $2 billion to $6 billion or more. Trump sued journalist Timothy L. O’Brien for libel after O’Brien wrote in a 2005 book that Trump may be worth as little as $150 million to $250 million. A Camden County, N.J., judge dismissed that suit in 2009, but Trump appealed. A three-judge panel heard the appeal earlier this month; a ruling is pending.

A former New York Times editor and now national editor of The Huffington Post, O’Brien relied in part on three confidential sources “with direct knowledge” of Trump’s finances who “had worked closely with him for years” in TrumpNation: The Art of Being the Donald, court records show.

In a deposition before lawyers representing the book’s publisher, Trump stated: “My net worth fluctuates, and it goes up and down with markets and with attitudes and feelings, even my own feelings.… Yes, even my own feelings, as to where the world is going, and that can change rapidly from day to day.”

A Trump press aide could not be reached for comment. Trump’s business history includes plenty of successes, including the millions he earns from licensing products and from his popular TV show The Apprentice. He’s argued that his business acumen would be one of his selling points as a candidate.

But as NBC News recently disclosed, Trump’s empire is littered with disgruntled investors, bankruptcies, lawsuits, and countersuits. He’s been investigated for deceptive business practices, and sued by prospective condo buyers, bond holders, students, and Deutsche Bank. His real estate properties are in many cases run by others. Some analysts argue the Trump brand has lost its luster.

Even if Trump has enough cash to go toe to toe with President Obama—and that’s a big if, given that the presumed Democratic nominee has set out to raise a record $1 billion—it may not help him much. Self-funded candidates typically lose at the polls, data shows. Of 52 self-financed candidates who ran for Congress in 2008, for example, fewer than a dozen went on to win, according to the Center for Responsive Politics.

Fundraising has a bad reputation, but it serves as a vehicle for listening to constituents and cultivating volunteers and grassroots support, said Jennifer A. Steen, an assistant professor of political science at Arizona State University: “In many ways, it really is basic politicking—going around and asking leaders and important groups to support you.”

Candidates who come straight to politics from the business world tend to be thin-skinned and to ignore expert advice, Steen said, pointing to failed California gubernatorial candidate Meg Whitman as an example. Whitman outspent Democratic nominee Jerry Brown by 15 to 1, investing a record $141.5 million of her own money. But her message failed to resonate.

The GOP field includes other potential self funders, of course, including Romney, who spent close to $40 million of his own money when he unsuccessfully sought the GOP presidential nomination in 2008, and businessman Jon Huntsman, the outgoing ambassador to China. Public disclosures identify Romney’s worth as ranging from $190 million and $250 million, and Huntsman’s as between $11 million and $74 million.

But Romney, for one, used his personal money “very shrewdly” to launch a grassroots fund raising operation in 2008, Steen noted. Romney raised $6.3 million last year, according to his campaign, and doled out more than $1 million of it to GOP candidates and causes.

As for Trump, Steen sees in him the stereotypical self funder: aloof, politically inexperienced, unaccustomed to taking criticism or advice.

“The pattern is unmistakable,” she said. “These people have common flaws, common deficiencies in their candidacies. And their ultimate electoral failure is entirely predictable.”

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