“The gap between what she says it will cost and what it will really cost is in the trillions of dollars, and the middle class will be on the hook to fill that gap,” says Jim Kessler, the executive vice president for policy at Third Way, a centrist Democratic group that has been critical of single-payer proposals. “My guess is that with accurate numbers, she’s somewhere between $5 trillion and $10 trillion short. [Her plan taps] the rich and corporations as much as possible. Who’s left? The middle class.”…

Larry Levitt, the executive vice president for health policy at the nonpartisan Kaiser Family Foundation, agrees that patients’ use would rise under a single-payer plan, which leaves the proposals dependent on a bet that government can substantially reduce payments across the medical system.

“The only way to make that math add up is to pay doctors and hospitals and drug companies a lot less, as Warren has proposed,” he told me. “The fundamental question here is: Can you lower health-care prices enough to offset the increased costs from universal coverage and very comprehensive benefits?”…

“You can do this mathematically. The question is: Can you do it in real life with real people?” says Nichols, who served as the senior health-policy adviser at the Office of Management and Budget in Bill Clinton’s administration. “When you talk about 110 percent of Medicare for hospitals and the same as Medicare for physicians, there are a lot of practices that would have to close up shop, lay people off.”