Massachusetts Senator Elizabeth Warren announces the suspension of her presidential campaign in front of her Cambridge, Massachusetts home on March 5, 2020. (PHOTO / AFP)

US Senator Elizabeth Warren endorsed former Vice President Joe Biden for president on Wednesday, delivering another high-profile backing from one of his former rivals as he aims to unify the Democratic Party ahead of a bruising contest with Republican President Donald Trump.

 Biden aims to unify the Democratic Party ahead of a bruising contest with Republican President Donald Trump

“In this moment of crisis, it’s more important than ever that the next president restores Americans’ faith in good, effective government — and I’ve seen Joe Biden help our nation rebuild,” Warren wrote in a tweet. “Today, I’m proud to endorse Joe Biden as President of the United States.”

Warren, a liberal who ended her own bid for the White House last month, gives Biden his third major endorsement of the week. Biden’s chief rival, Bernie Sanders, endorsed him on Monday after suspending his campaign last week, while former President Barack Obama backed Biden on Tuesday.

READ MORE: In bid for unity, ex-rival Sanders backs Biden to challenge Trump

In recent weeks, the more moderate Biden has made overtures to liberal backers of Sanders and Warren. After Sanders’ departure from the race, Biden’s campaign shifted left on two of his top priorities, student debt and Medicare, and the two men said during a joint video appearance on Monday that they would create working groups to address major policy areas.

In a video announcing her endorsement, Warren noted she didn’t agree with Biden all the time but praised his willingness to adapt

In a video announcing her endorsement, Warren noted she didn’t agree with Biden all the time but praised his willingness to adapt.

“One thing I appreciate about Joe Biden is he will always tell you where he stands,” she said. “When you disagree - he’ll listen. ... And he’s 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.”

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Biden also adopted Warren’s sweeping plan on bankruptcy, a striking move given that the two rivals had clashed for more than a decade over legislation that Biden backed making it harder to file for bankruptcy protection.

Biden and Warren have had “several calls” since she ended her campaign, a source familiar with the discussions told Reuters.