As the war of words in the Democratic primary race escalates between Hillary Clinton and Bernie Sanders, the Vermont senator is reminding people of how Clinton used to praise his views on health care.

On Wednesday, Sanders posted on Twitter an autographed photo from Clinton in 1993 that said “thanks for your commitment to real health care access for all Americans.”

“To Bernie Sanders with thanks for your commitment to real health care access for all Americans…”-@HillaryClinton pic.twitter.com/XMVPEx8fT8 — Bernie Sanders (@BernieSanders) January 13, 2016

Sanders, a self-described Democratic socialist, wants a government-run single-payer health care system. This week, Clinton’s daughter, Chelsea, used that to accuse Sanders of wanting to do away with Obamacare since that would get rid of private health insurance.

[dcquiz] “I never thought that I would be arguing about the Affordable Care Act or Obamacare in the Democratic primary,” Chelsea Clinton said. “Senator Sanders wants to dismantle Obamacare, dismantle the CHIP program, dismantle Medicare and private insurance.”

Clinton’s campaign is ramping up its attack on Sanders’ health care plan with a planned conference call with reporters Wednesday to “outline Sen. Bernie Sanders’ shifting answers and lack of clarity on how he would pay for his health care plan.” (VIDEO: Bloomberg’s Hunt: ‘No Excitement’ For Hillary Among Young Voters)

Michael Briggs, a spokesman for Sanders, said Wednesday: “Every proposal Senator Sanders has introduced in this campaign has been paid for. We hope the Clinton campaign will stop engaging in false and misleading attacks and instead provide similar clarity on how their proposals will actually be paid for.”

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