Sen. Elizabeth Warren (D-Massachusetts) endorsed former Vice President Joe Biden on Wednesday in an attempt to unify Democratic voters this November.

“We’re all in this together now,” Warren said in a video posted on Twitter. “And now, it’s up to all of us to help make Joe Biden the next president of the United States. Let’s get to work.”

Her endorsement came almost immediately after former President Barack Obama and former Democratic frontrunner Sen. Bernie Sanders (I-Vermont) both offered their endorsements of Biden. Now, every major Democratic candidate except Marianne Williamson and New York City Mayor Bill de Blasio have endorsed Biden.

Her video attempted to assuage progressive voters concerned about his more moderate policy ideas.

“When you disagree, he’ll listen — not just listen, but really hear you,” Warren said. “And he has shown throughout this campaign that when you come up with new facts or a good argument, he’s not too afraid or too proud to be persuaded.”

Warren had initially declined to offer an endorsement after she dropped out, but now that Biden is the only remaining candidate, the need for unity behind one front was apparent.

Biden thanked Warren for her endorsement in a tweet on Wednesday, calling her “the fiercest of fighters.”

“We are in a battle for the soul of this nation and I’m proud to have the fiercest of fighters, Senator [Warren], on my side,” Biden wrote. “With her help, we’re going to beat Donald Trump and create a government that works for everyone — not just the wealthy and well-connected,” he wrote, parroting one of Warren’s signature lines from the campaign trail.