Sen. Elizabeth Warren, D-Mass., has come to a "make-or-break" moment in her campaign, Fox Business Network host Charles Payne said Friday, as the top presidential contender struggles to explain how she'll pay for a "Medicare-for-All" health care plan.

The issue centers around whether such a plan, estimated to cost $32-34 trillion over 10 years, can be sufficiently funded without significant tax increases on the middle class.

Warren has been asked for an explanation 17 times on the campaign trail, "America's Newsroom" host Sandra Smith noted, including at a debate last week. She has vowed to "soon" release a detailed plan and claimed that health care costs for Americans will go down dramatically, blunting any tax hikes.

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"This has become the make-or-break moment for her presidential ambitions," said Payne, the host of "Making Money."

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Payne said the $34 trillion is for "Medicare-for-All" but Warren has also promised many other "goodies" to voters. He said she now needs to "pull a rabbit out of her hat" or risk being "boxed in" on the issue.

"It may have to be a mea culpa," said Payne, wondering whether Warren will have to commit to a tax hike of some kind.

On the debate stage last week, Warren faced biting criticism from some of her rivals, including Sen. Amy Klobuchar and Pete Buttigieg, who accused her of being dishonest about the plan's costs.

Accusing Warren of being evasive, Buttigieg argued that “your signature, Senator, is to have a plan for everything— except for this. No plan has been laid out to explain how a multitrillion-dollar hole in this Medicare-for-all plan that Senator Warren is putting forward is supposed to get filled in.”

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In a Fox News op-ed, Grover Norquist, the president of Americans for Tax Reform, laid out why Warren cannot fund her plans only by taxing corporations and the wealthy.

"Warren has extraordinarily expensive big plans, funded courtesy of your wallet. Her plans will intrude into every aspect of American life," he wrote.

A new national poll found Warren with a seven-point lead over Joe Biden, with Sen. Bernie Sanders trailing by 13 points.