Sen. Elizabeth Warren endorsed former Vice President Joe Biden for president, becoming the last major presidential contender to formally throw her support behind the presumptive Democratic nominee as he swiftly moves to unite the party.

In a Wednesday morning video posted to Twitter , the Massachusetts senator touted Biden as a dedicated public servant known for his empathy, which she believes is critical, particularly as the country fights the coronavirus pandemic. She specifically pointed to his experience handling past crises and tragedies like the 2013 Boston Marathon bombings and the Great Recession.

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Over the past few days, Biden has nabbed several high-profile endorsements including from former President Barack Obama and Sen. Bernie Sanders of Vermont in hopes of uniting different factions of the party ahead of the general election against President Donald Trump.

"Joe Biden has spent nearly his entire life in public service. He knows that a government run with integrity, competence and heart will save lives and save livelihoods," Warren said. "And that's why I'm proud to endorse Joe Biden as president of the United States."

"But when Donald Trump is gone, we will need to do more than heal a nation that has been bitterly divided," she continued. "We will need to rebuild and transform our country. And I've seen Joe Biden help a nation rebuild."

Warren, who was once considered a front-runner for the Democratic nomination, dropped out of the race in early March after a disappointing finish in several primaries and caucuses. She declined to endorse when the race came down to Biden and Sanders.