Hillary Clinton is not onlysaying that Bernie Sanders vision of a single-payer health caresystem is unrealistic, but that it, if implemented,would be a disaster for those it intends to help.

At the last debate between the two candidates for the Democraticnomination, Clinton, who has lost six consecutive primaries to heropponent, sought to portray Sanders’ policies not only asunachievable, but fundamentally flawed.

Clinton referenced a recent column in the WashingtonPost, by Max Ehrenfreund, which argued that Sanders’ healthplan would cost more for low-income Americans than the status quo.Millions who are currently enrolled in Medicaid already pay verylittle for care, Ehrenfreund pointed out, but they would end uppaying more in payroll taxes to finance Sanders' single-payersystem.

“The Washington Post called it a ‘train wreck for thepoor,’” said Clinton during the debate.

She further chided Sanders for not being upfront about the costsof his ambitious overhauls of public services, including healthcare and higher education.

“I do think when you make proposals and you’re running forpresident, you should be held accountable for whether or not thenumbers add up, and whether or not the plans are actually going towork,” she said.

In past encounters, Clinton has suggested that Sanders’ plan toput in place an entirely new health care system would endanger theprogress made towards universal coverage through the PatientProtection and Affordable Care Act (PPACA). He has called thecriticism absurd, saying that there would be no scenario in whichthe PPACA would be scrapped if he cannot achieve his“Medicare-for-all” vision.

As he has in past debates, Sanders highlighted the factthat governments in other western countries guarantee coverage totheir citizens, while spending far less on health care overall. Hesuggested that reluctance to embrace a single-payer system was dueto fear of taking on the insurance industry.

“What Secretary Clinton is saying is that we are not a countrythat has the courage to stand up to big money and do what has to bedone for the working families of this country,” he said.

Despite the string of recent defeats, Clinton remains the clearfrontrunner for the Democratic nomination, with a sizeable leadamong delegates.

Unlike the race for the Republican nomination, which hasincluded a number of “winner-take-all” contests, every Democraticprimary and caucus has awarded delegates to the candidates based onthe proportion of the vote they receive. As a result, Clinton hasstill picked up a fair share of the delegates even in the statesshe has lost. Polls also suggest she will win the upcoming primaryin New York by a comfortable margin.