LOS ANGELES (CBS / AP) — Billionaire Mike Bloomberg has ended his bid for the Democratic presidential nomination and has endorsed Joe Biden.

It was a stunning collapse for the former New York City mayor, who had pinned his 2020 hopes on the Super Tuesday states and drained more than $500 million from his own fortune into his ultimately unsuccessful campaign, much of it on television ads and mailers.

Bloomberg announced his departure Wednesday after a disappointing finish on Super Tuesday in the slate of states that account for almost one-third of the total delegates available in the Democratic nominating contest.

As of early Wednesday, Bloomberg received 14.3 percent of the vote in California, far behind Vermont Sen. Bernie Sanders and Biden.

During his brief presidential run, Bloomberg’s bulk of endorsements came from mayors, including San Francisco Mayor London Breed and San Jose Mayor Sam Liccardo.

Some of his former Democratic rivals had coalesced around Biden as the moderate alternative to Sanders.

© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.