But despite blanketing the airwaves with a huge advertising blitz, he was a long way short of his dream of elbowing Mr Biden aside and turning the race into a straight fight with Mr Sanders.
Written off as politically dead less than a week ago, Mr Biden rallied moderate voters to his side and halted the Vermont senator’s bid to use Super Tuesday to open up a potentially unbridgeable lead in delegates to the Democratic convention where the party will pick its candidate to take on Donald Trump.
The fates of Mr Biden and Mr Bloomberg have long been intertwined. The latter stayed out of the contest in early 2019 when the former Vice President looked like he would walk away with the nomination.
Mr Bloomberg joined the race last autumn as Mr Biden began to stumble and then briefly surged after he was humiliated in Iowa and New Hampshire.
But a disastrous debate performance in Las Vegas last month broke Mr Bloomberg’s stride, allowing Mr Biden the time to steady himself and, thanks to his strong support among African American voters, effectively relaunch his campaign in South Carolina last weekend.
Although boosted by a win in California, Mr Sanders now undoubtedly has a real battle on his hands. Mr Biden’s strong performance on Super Tuesday — he won 10 states to Mr Sanders’ four and crucially now leads the delegate table — was all the more impressive given that his cash-strapped campaign was comprehensively outspent and out-organised by both Mr Bloomberg and the Vermont senator.
Mr Sanders also no longer has the advantage of a crowded moderate field splintering his opponent’s vote. Former contenders Pete Buttigieg and Amy Klobuchar lent their support to Mr Biden on the eve of Super Tuesday and Mr Bloomberg may now come under pressure to stand aside too.
If he does, he’s likely to further assist the former Vice President by turning his considerable financial firepower on the self-proclaimed “democratic socialist” whose nomination, he believes, would guarantee Mr Trump’s re-election.
Finally, for all the enthusiasm of his supporters and the financial war chest he has amassed, the race to date has exposed Mr Sanders’ electoral Achilles heel.
As in 2016, when he ran against Hillary Clinton for the nomination, Mr Sanders lacks support among the Democratic party’s most loyal constituency, African American voters.
In South Carolina, Mr Biden beat him by four to one among this key group and they helped deliver Barack Obama’s loyal Vice President big wins across the southern Super Tuesday states.
Moreover, Mr Sanders’ pitch that his left-wing populism would mobilise high turnout among young voters has thus far failed to materialise. He won the youth vote but Super Tuesday exit polls showed only one in eight voters were aged under 30 with nearly two-thirds over 45.
He also faces difficult terrain over the next month as the contest moves through states many, if not all, of which opted for Mrs Clinton over Mr Sanders four years ago.
But, like the current occupant of the White House, Mr Sanders is a master of the politics of grievance. A 30-year veteran of Capitol Hill, he growled earlier this week about “establishment politicians” rowing in behind Mr Biden. That message may yet resonate with many voters.
