Billionaire Michael Bloomberg has ended his bid for the Democratic presidential nomination and endorsed former US vice president Joe Biden.
It was a stunning collapse for the former New York City mayor, who had his 2020 hopes on the Super Tuesday states.
So much so, that the billionaire pumped more than £390 million ($500 million) of his own fortune into the campaign.
Mr Bloomberg announced his departure from the race after a disappointing finish on Super Tuesday - when millions vote in 16 states, territories, and groups accounting for almost one-third of the total delegates available in the Democratic nominating contest.
The two states with the most delegates - California and Texas - cast their votes on Super Tuesday - the results could well decide who faces Donald Trump in the November presidential election.
While Joe Biden's performance in Super Tuesday was hailed as one of the most surprising political recoveries in recent American history, Mr Bloomberg won only in the territory of American Samoa.
The billionaire picked up several dozen delegates elsewhere but it was a disappointing result for the Bloomberg campaign.
In a statement on his website, Mr Bloomberg said: "Three months ago, I entered the race for President to defeat Donald Trump.
"Today, I am leaving the race for the same reason: to defeat Donald Trump".
President Trump has been a vocal critic of Mr Bloomberg, labelling him "Mini Mike Bloomberg" in a series of tweets about the former New York City mayor.
In his statement, Mr Bloomberg gave his backing to Democrat contender Joe Biden, describing the former US vice president as "my friend and a great American".
The billionaire said he would "continue to work for sensible, common sense policy solutions" including issues on gun safety laws, climate change, healthcare, and further education.
Mr Bloomberg had faced stinging criticism from fellow contenders earlier in the contest.
Senator Elizabeth Warren accused the former New York mayor of using crude and sexist language, while others criticised what they said were racist policies during his time as mayor.
Senator Elizabeth Warren attacks Mike Bloomberg in the Las Vegas Democratic debate:
Mr Biden won big in Southern states on Super Tuesday - states where Mr Bloomberg had poured tens of millions of dollars and even cautiously hoped for a victory.
Two other former Democratic rivals, Amy Klobuchar and Pete Buttigieg, dropped out of the race and endorsed Mr Biden as the moderate alternative to Vermont Senator Bernie Sanders just the day before Super Tuesday.