What she's saying: During the event in New York, Clinton said in response to a question on whether she could "get behind" the plan, "If it were to go to Senate ... if you had a president who pushed to present it, I would be very much in favor of whatever the debate was."

The 2016 Democratic presidential candidate added that while she doesn't think it would pass, it was the "right goal" and the current health care debate among Democrats is healthy.

"The Affordable Care Act took us to 90% of coverage — the highest we had ever gotten in our country after many, many efforts including one I was involved in more than 25 years ago," Clinton said.

"We have a 10% gap to fill and we have a lot of learning to do about the best way not only to fill the gap, but then to drive down costs as much as it is possible without undermining quality advancements."

Why it matters: Clinton is the latest in a line of current and former officials and lawmakers to question how workable Warren's plan would be in practice. Warren has faced criticism from her closest Democratic presidential rivals and others on the issue of cost to taxpayers.

Per Axios' Caitlin Owens, "We've never tried any cost containment measures that are remotely close to being as aggressive as Warren's, and there could be consequences if payment rates are slashed so low."

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