© Greg Nash Warren attacks Bernie at debate, says his team 'trashed' her

Sen. Elizabeth Warren (D-Mass.) began Tuesday's South Carolina debate with an attack on fellow progressive Sen. Bernie Sanders (I-Vt.), saying his team "trashed" her on universal health care.

"Bernie and I both want to see universal health care, but Bernie's plan doesn't explain how to get there, doesn't show how we're going to get enough allies into it, and doesn't show enough how we're going to pay for it," Warren said at the CBS News forum in Charleston, S.C.

"I dug in. I did the work, and then Bernie's team trashed me for it," she continued. "We need a president who is going to dig in, do the hard work, actually get it done. Progressives have got one shot, and we need to spend it with a leader who will get something done."

The attack was noteworthy as Warren has generally not gone after Sanders on the debate stage. But Sanders over the last month has become the clear frontrunner in the race, and he has been the subject of attacks from all of the other candidates on stage Tuesday.

"Bernie and I agree on a lot of things, but I think I would make a better president than Bernie," Warren said. "The reason for that is getting a progressive agenda enacted is really hard, and it's going to take someone who digs into the details to make it happen."

Warren's attack on Sanders comes as he continues to cement his status as the frontrunner in the Democratic primary, as she loses ground as the race's prominent progressive.

Sanders has faced pressure from his rivals to explain how he will pass and pay for a number of his proposals, including Medicare for All.

The progressive senator released a list of how he plans to pay for his proposals on Monday night.