The billionaire businessman’s ambitious experiment bombed: He didn’t win a single Super Tuesday state, emerging victorious only in American Samoa — a devastating return on his investment of more than half a billion dollars.

Bloomberg placed third or fourth in every state, and he trailed the two leaders by hundreds in the delegate count. His chances would not improve if he continued campaigning. In fact, doing so could hurt Joe Biden, the leading moderate in the race, his advisers reasoned, despite Bloomberg’s demand earlier in the day that reporters ask Biden why he wouldn't drop out for Bloomberg.

So the former mayor flew back to New York City with his family on a private jet Tuesday evening and huddled early Wednesday morning with his closest advisers in one of his Manhattan offices. Alongside campaign manager Kevin Sheekey, chair Patti Harris and adviser Howard Wolfson, Bloomberg reviewed the final results from the biggest night of the Democratic primary, one that was essential to his strategy to win the nomination.

They saw no path to success. Democratic voters had been inundated with the most positive — and occasionally misleading — messages money could buy, and they still roundly rejected him. He then opted to drop out of the race and throw his support — and potentially his vast resources — behind Biden in an effort to halt Bernie Sanders’s surge and realize his ultimate goal of defeating President Trump in November.

“Obviously, last night did not go as we hoped,” Sheekey, who has been encouraging Bloomberg to run for president since 2007, told Bloomberg staffers on a conference call late Wednesday morning.

Sheekey said he hadn’t expected Bloomberg to run for president in the first place.

The billionaire had just spent more than $115 million to help elect a Democratic-controlled House of Representatives, combing through dozens of races before sinking his fortune into two dozen of them.

When Bloomberg’s own race was over, Sheekey tried to frame the campaign as a valiant, even historic, effort to ensure there was ample early pressure on Trump.

“Mike went from 1 percent in the polls to a serious contender for the Democratic nomination at a point in our history that I quite frankly have never known to be more important,” Sheekey said. “We surged past some really good candidates who have been at this for well over a year. And yesterday, nearly 2 million Americans cast their vote for Mike from all over the country.”

Bloomberg — who disdains partisan politics and only re-joined the Democratic Party in 2018 when he was contemplating a White House bid — enjoyed a rapid surge after his Nov. 24 entry into the crowded field. He apologized for a race-based policing strategy he oversaw as New York City mayor, saturated air waves across the country with ads and amassed a campaign apparatus of more than 2,400 staffers across 43 states, giving him time to lay groundwork while his competitors duked it out in Iowa.

Bloomberg started with a record-breaking ad buy of $34 million. The blitz was aimed at attracting African-American and Latino voters, two demographic groups key to winning the nomination. It was his means of catching up with those at the top of the Democratic ticket and for a while, polls showed that it may have worked in his favor: by the end of January,he polled in double digits, just behind Elizabeth Warren. By mid-February, he was the top choice among 20 percent of black voters.

He spent nearly $200 million in Super Tuesday states, including more than $30 million in the South, but he only crossed the 15 percent threshold in two Southern states.

He reasoned that he could skip the first four voting states in favor of delegate-rich ones that vote on Super Tuesday. In recent weeks, at least two high-ranking campaign advisers have privately questioned his decision not to compete in South Carolina, where they believe he could have done well.

The strategy seemed to be working in his favor until mid-February, when a 2015 audio clip of Bloomberg making charged remarks about young black and Latino men surfaced online. Bloomberg struggled to contain the fallout, as leaders for his black and Latino constituency teams gathered on a call with staffers around the country to calm their nerves.

In a conference room at his Times Square headquarters, Bloomberg assembled black pastors for a previously scheduled meeting that lasted more than two hours and included face time with the candidate. In a sign of the pressure to come, the recording was quickly raised.

Things got worse when he stepped onto a national debate stage after persuading the Democratic National Committee to alter the qualifying rules to allow entry for a self-funded candidate who did not accept outside donations.

That gamble proved disastrous.

Bloomberg was almost immediately knocked on his heels by rival Elizabeth Warren over complaints about treatment of women at his eponymous financial news service company — claims he settled years ago with payouts and non-disclosure agreements that Warren’s grilling forced him to agree to lift.

Sanders and others attacked his personal wealth, which totals more than $60 billion, insisting he knows nothing of the problems facing the majority of Americans he wanted to lead.

Bloomberg, who at 78 years old wasn’t about to change his personality, let his irritability seep through. Defensive and annoyed, he referred to the comments he made to female employees as “jokes” and he said he couldn’t release his tax returns yet because he could not use TurboTax — a popular tax preparation service among many Americans.

Afterwards, Bloomberg tried to reverse his fortunes by identifying three confidentiality agreements with women related to alleged comments he made, and inviting them to be released from the pacts.

He never recovered from the evening.

“A lot of people thought we were running as Biden’s understudy, and they were sort of right,” said one aide. “When he collapsed in Iowa and New Hampshire, we surged. When Biden had a comeback in South Carolina, we cratered. I don’t think most people expected the moderate wing to be frantically trying to stop Bernie on Super Tuesday, but that’s what it came down to, and it was out of our control.”

Two other campaign aides said the first debate performance reversed his climb, even as he rebounded for a better showing in a second debate and pivoted to the message that Americans want a “commander in chief,” not a “debater in chief.”

Some political insiders have questioned why his team put him on a debate stage at all, knowing his vulnerabilities would be laid bare and he wasn’t inclined to soften his matter-of-fact attitude or contain his eye rolls. To that end, several campaign aides said every focus group and poll showed voters were demanding to see him participate in the grueling face-offs.

Then came South Carolina, where Biden resurrected his collapsing campaign with a blowout victory that demonstrated his dominance with black voters who are key to winning a Democratic nomination. Biden seized almost 50 percent of the vote Saturday night — and nearly two-thirds among African Americans — as Bloomberg was crisscrossing the Deep South in futile search of the same supporters.

Bloomberg’s internal polls showed him in free fall and his aides said that after South Carolina, they knew it would be difficult to survive Biden’s ascent.

They saw no path, but did not want to drop out before he had an opportunity to test his theory that with virtually unlimited resources he could build support without competing in the first four voting states. It was a humbling end for a man who insisted he was the best option to challenge Trump.

Bloomberg had first aimed his fire at Trump in a prime-time Democratic National Convention speech in 2016 that was more about eviscerating the current president than elevating Hillary Clinton. He even took the opportunity to remind viewers he doesn’t favor partisan politics.

But he did not opt to challenge Trump until his team said internal polling showed Biden weakening and the moderate lane opening. Once he got in the contest, Bloomberg essentially ran a general election campaign — spending his energy on Trump instead of the field of Democrats he would have to defeat.

The left wing of the party, however, was having none of it and moderates rekindled their affection for Biden. But Bloomberg did attract some moderate Republicans who showed up to his events, saying he was the only Democrat they would cross the aisle for.

“I switched parties because I’ve had enough of Donald Trump. He’s not professional, he’s certainly not presidential,” Mike Vaughn, a 57-year-old Florida resident, said at Bloomberg’s party Tuesday night. “Mike has always gotten things done and I think he’s the absolute best candidate. I switched parties in order to vote for this man.”

Bloomberg spoke Wednesday morning with Biden, an aide told POLITICO. “I’ve known Joe for a very long time. I know his decency, his honesty, and his commitment to the issues that are so important to our country — including gun safety, health care, climate change, and good jobs,” he wrote in the statement announcing his decision.

Bloomberg aides said it was still unclear how he’d be involved in Biden’s campaign. Advisers on the all-staff call said they are working on a plan for how they'll wind down the campaign. The advisers stressed they built their massive operation to continue the fight against Trump in battlegrounds regardless of whether he’s the nominee.

“We’re going to do that, as promised,” said Dan Kanninen, the states director, adding that organizers on the ground throughout the states will be given the opportunity to continue working on the effort. “Obviously, that means we’re shifting this entire operation to do that and it will take a little bit of time for us to figure out exactly how that looks,” Kanninen added.

Sheekey suggested the transition would happen fast.

"This is a large enterprise that we will have to transition quickly and we will begin that today,” he concluded. “But Mike, myself, the team here, and I hope all of us, stay off the sidelines and stay in this fight to do everything that we possibly can to the best of our ability — just as you have — going forward.”

Maya King contributed to this report.