A massive group of House Democrats—totaling at least 70 members in all—signed onto the establishment of a Medicare for All caucus Thursday morning, signaling the increasing feasibility of the policy among members.

The caucus, co-chaired by Rep. Pramila Jayapal (D-WA), Rep. Keith Ellison (D-MN) and Rep. Debbie Dingell (D-MI), is intended to help “build the evidence base” for a Medicare for All proposal, Jayapal said at a press conference announcing the formation of the group.

“Our goal is to sponsor briefings in this caucus on a variety of topics from the basics of Medicare for All to financing to universal health care systems around the world,” Jayapal continued.

The members who have signed on to the caucus, the formation of which was first reported by Vice News, represent a wide swath of the United States, including more senior members and some fresher faces. And already more than a third of all House Democrats have signed on to join.

Those names include Rep. Ro Khanna (D-CA), a freshman from California; Rep. Barbara Lee (D-CA), a stalwart progressive who has been discussed as a possible next Speaker of the House; and Rep. Tim Ryan (D-OH), who previously challenged Rep. Nancy Pelosi (D-CA) for House minority leadership.

In addition to this caucus, there already exists legislation in the House to establish a Medicare for All system, with 122 co-sponsors signed on. Over on the Senate side, Sen. Bernie Sanders’ Medicare for All bill has the sponsorship of at least a third of Senate Democrats.