Washington (CNN) Rep. Pramila Jayapal, the co-chair of the Congressional Progressive Caucus, is endorsing Bernie Sanders for president and will become his national health policy chair, the Sanders campaign confirmed Sunday.

Jayapal's decision means Sanders now has the backing of both CPC co-chairs. Wisconsin Rep. Mark Pocan announced his endorsement of Sanders last week. Reps. Alexandria Ocasio-Cortez, who tweeted that Jayapal's support was a "really big deal," Ilhan Omar and Rashida Tlaib lined up behind the Vermont senator last year.

Jayapal, representing Washington state, is the lead sponsor of the House "Medicare for All" bill and had been courted by both Sanders and Massachusetts Sen. Elizabeth Warren, for whom she issued a key statement of support in November amid criticism on the left of Warren's revised Medicare for All "transition" plan.

"I'm all in for @BernieSanders for President!," Jayapal tweeted on Sunday. "Bernie has the bold passion, authenticity & clarity that working people across this country desperately need. We are building the progressive movement that will bring justice & opportunity & transform our country. Join us!"

Speaking to reporters in Conway, New Hampshire, on Sunday, Sanders said he was "very proud" to have Jayapal's endorsement while touting her advocacy of "Medicare for All."

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