REVEALED: The cunning ploy devious Democrats used to sabotage Biden's campaign and their bombshell threat if he didn't drop out of race

The Democrat Party plot to get Joe Biden to drop out has been long in the works, a Biden insider claims. 

That plan came to fruition on Sunday, when the 81-year-old president dramatically announced the end of his campaign before endorsing Vice President Kamala Harris. 

However, a source close to Biden's family is saying that the party put together a 'palace coup' over the course of recent weeks, with the president fighting it until he was threatened with being forced out.

The insider says that the disastrous debate against Donald Trump on June 27 - the earliest presidential debate in history - was part of the strategy, despite being publicly requested by Biden on social media.

'That debate was a set-up to convince Democrats that he couldn't run for president,' the source told the New York Post. 

Biden was often seen on split screen with his mouth agape and a blank stare during the showdown against Trump last month, immediately sending Democrats into a freak out.

Though publicly, most of the faces of the left stayed behind Biden, in the shadows, party powerbrokers were threatening to invoke the 25th amendment. 

Section 4 of the amendment allows for removal of a president who is deemed incapacitated by any kind of illness, injury, or mental impairment. 

One of the few trusted by Biden who believed he was being pushed out: troubled son Hunter, who became a gatekeeper for his father after the debate.

'Hunter felt he was being set up and he was very concerned about his father. These people, these officials were not on Joe's side,' the source claimed.

They also said that it might not be a straight shot to the nomination for Harris, despite Biden's endorsement. 

The source claimed that Senator Mark Kelly of Arizona may be a popular pick of delegates, though the former astronaut has already endorsed Harris. 

Once Biden was finally, officially convinced to get out, everything moved at the speed of light. 

He was isolating with COVID at his $3.4 million holiday home in Rehoboth Beach, Delaware, when his shrinking inner circle handed him polling data showing he could no longer beat Donald Trump. 

That was when they composed a letter saying it was time for him to step aside for the good of the future of the Democratic party. 

Donors had pulled millions of dollars in funds, the list of Democrats telling him to drop out was growing by the day, and polls suggested that his chances of beating Donald Trump were dwindling after his disastrous debate performance.

Biden had previously insisted that he would only step aside if he was shown polling that proved Kamala Harris would fare better than him against Trump, or if he developed a 'medical condition'. In the end, it was the first of those developments that sealed his fate. 

Biden went to bed on Saturday night at the beach house, knowing he would announce his bombshell the next day.

At 1:45 pm on Sunday he began calling his senior staff at the White House and the campaign.

By that time he had already told Harris and Senate Majority Leader Chuck Schumer. 

At 1:46 pm, his campaign account posted a letter from the president announcing his decision even as he was still on the staff call.

Most of his staff – both in the White House and at the campaign - were shocked. They learned the news online, getting the alert when the @JoeBiden account posted the president's missive.

It capped a chaotic 48 hours for the Biden family as they hunkered in behind their patriarch with a small, inner circle of longtime aides supporting them. Some were even reporting back to Jill Biden about those staffers deemed disloyal.

Meanwhile, Biden had veered from angry at the pressure from his party to acceptance of the situation.

And once his final decision was made on Saturday night, the rest moved quickly. 

Biden called Harris directly to tell her the news.

He also had one-on-one calls with White House chief of staff Jeff Zients and campaign chair Jen O'Malley Dillon, according to reports. He would also speak with his Cabinet, Members of Congress, governors, and supporters.

But it all happened so fast many staff were hurt about the way they learned of the news, although they weren't surprised by it. 

Harris then announced she was running for the Democratic presidential nomination.