Sen. Bernie Sanders, I-Vt., turned up the heat on the Democratic debate stage on Tuesday as he vehemently defended his plan for reforming health care amid attacks from several of his fellow contenders.

He was responding to Rep. Tim Ryan, D-Ohio, who told the Vermont senator he didn't "know" that "Medicare-for-all" would provide certain benefits. "I wrote the damn bill!" Sanders exclaimed in response.

His comments came during a long, contentious exchange in which candidates clashed over competing visions for health care. Sanders has championed the Medicare-for-all program with his own bill in the Senate and, along with Sen. Elizabeth Warren, D-Mass., is perhaps its most vociferous proponent in the Democratic field.

Sanders' team, on Twitter, doubled down on his fiery statement during the debate.

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"Medicare-for-all means expanding benefits to include dental care, eyeglasses and hearing aids. I know that because I wrote the damn bill. #DemDebate," a tweet read.

His team also tweeted his disappointment with former Rep. John Delaney, D-Md., whom he claimed spouted falsehoods about hospitals closing under his health care plan.

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"It's disappointing to see some Democrats repeating a lie you normally hear from health insurance lobbyists to attack Medicare for All," one read, linking to a PolitiFact article on Delaney's claim.

The debate came just a day after the Mercatus Center released a study that estimated Sanders' plan would cost $32.6 trillion over 10 years. By 2031, the costs would reportedly reach nearly 12.7 percent of GDP.

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Former Colorado Gov. John Hickenlooper, during the debate, also pushed back on large programs like "Medicare for all," arguing that it limited choice for Americans seeking health coverage. He and Delaney have been outspoken critics of the more progressive positions in the Democratic field.

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Delaney, in particular, portrayed Sanders and Warren as attempting to take away private insurance from American citizens.

Fox News' Brooke Singman contributed to this report.