Dying healthcare rights activist Ady Barkan announced he was "all in" for Sen. Bernie Sanders on Thursday, just hours after the candidate he earlier endorsed, Sen. Elizabeth Warren, dropped out of the 2020 Democratic presidential primary.

While Barkan—who found the Be a Hero organization to advocate for progressive issues, including Medicare for All—endorsed Warren over Sanders in November, he says now there is only one candidate in the Democratic race with the kind of vision he believes is needed in the White House.

Sanders, said Barkan: "has reshaped American politics. Reshaped what we think is possible. Reshaped how we dare to dream. But, of course, it's not about him. It's about us.

@BernieSanders has done more than anyone else to build the movement for #MedicareForAll. He has reshaped American politics. Reshaped what we think is possible. Reshaped how we dare to dream. But, of course, it's not about him. It's about us. SCROLL TO CONTINUE WITH CONTENT Never Miss a Beat. Get our best delivered to your inbox.





And I'm all in. pic.twitter.com/u7Nctfhvp0 — Ady Barkan(@AdyBarkan) March 5, 2020

In an earlier tweet, Barkan thank Warren for her inspiring campaign. "Your candidacy has been simply stunning: From your historic platform to your exceptional modeling of what it means to be humble and open to critique to your repeated recounting of the history of America's freedom fighters," Barkan said, addressing the Senator. "You have so much to be proud of."

The fresh endorsement of Sanders comes as progressives nationwide on Thursday urged Warren to join forces with the Vermont Senator to take on former Vice President Joe Biden and the corporate establishment that has now rallied around him.