Calls for President Joe Biden to drop out of the 2024 presidential race ramped up in a big way after his debate last month with former President Donald Trump. 

Despite intensifying pressure from within the highest echelons of the Democratic Party, the elderly president and his campaign insisted that he was in it to win it -- until he suddenly wasn't.

According to the Daily Mail, the president reportedly made a shocking, last-minute decision on Sunday to withdrawal from the presidential race, which was described as a move that "blindsided" the White House and top staffers.

The decision reportedly came after his aides and advisers reminded him that donors were pulling out left and right, and polling data increasingly showed him being beaten -- badly -- by Trump in November.

He finally called it

Sources familiar with the president's decision to bow out said that First Lady Jill Biden was by his side as he made the last-minute decision to get out of the race.

"Down to the last hours of the decision only he could make, she (Jill Biden) was supportive of whatever road he chose," a Jill Biden spokeswoman said. "She’s his biggest believer, champion, and always on his side, in that trusted way only a spouse of almost 50 years can be."

The Daily Mail recapped how Biden's decision was ultimately made while he was isolating at his Delaware home because of COVID.

On Saturday evening, Biden summoned to his side two men who have been there since his political start: advisers Steve Ricchetti and Mike Donilon. They have been with him through the best of times - his first years as a senator - and the worst of times - the death of his son Beau Biden in 2015.

The outlet added:

Already with the president and the first lady were their closest aides Annie Tomasini and Anthony Bernal, who they refer to as 'family.'

It was Ricchetti and Donilon who brought with them devastating new data which would help to make up Biden's mind. They revealed the latest internal campaign polling, taken since the debate, which showed he could no longer beat Trump.

Ricchetti and Donilon were then asked to draft a letter announcing Biden's decision to pull out of the race, which was posted on the president's X account the next day.

The move reportedly came as unexpected for much of the White House staff, even amid the mounting pressure.

"Shocked"

White House staffers have claimed that nobody there knew it was coming and they all learned that Biden had decided to drop out after he posted the announcement on his X account.

"No one had a heads up before the tweet posted," one staffer reportedly said.

They added, "Which, to me, is an insane way to treat the 1300 people that work for you on the campaign."

Shortly after the announcement, Biden offered his full endorsement of Vice President Kamala Harris. Only time will tell if she'll sit at the top of the ticket in November.