Billionaire Michael Bloomberg has ended his campaign for the Democratic presidential nomination. The former Republican mayor of New York repeatedly teared up Wednesday as he thanked staffers in his Manhattan campaign headquarters, before throwing his support to Joe Biden.

Michael Bloomberg: “I’ve always believed that defeating Donald Trump starts with uniting behind the candidate with the best shot to do it. And after yesterday’s vote, it is clear: that candidate is my friend and a great American, Joe Biden.”

Bloomberg, with a net worth of about $64 billion, is the ninth-richest person on Earth. He spent more than $550 million in just over three months of campaigning. He’s previously committed to spending as much as $2 billion to defeat Trump, and could use some of his wealth to set up a super PAC to pay for new attack ads against Biden’s main opponent, Bernie Sanders.