Trump and his allies go after Biden's cognitive state with huge ad buy

Former President Trump's week and a half of keeping a relatively more restrained profile following his debate with President Biden appears to be coming to an end.

The presumptive Republican presidential nominee is expected at a rally Tuesday evening near Miami, Florida, to take aim at Biden's extremely uneven debate performance. 

And the Trump campaign says the former president will "lay out an indictment" on what he claims is an attempt by the Biden campaign, the Democratic Party, and the mainstream media to cover up what he argues is the 81-year-old president's cognitive decline.

A campaign aide, who asked for anonymity to speak more freely, said Trump will "press the case that Biden and the Democrats, with the collusion of mainstream media, have perpetrated a fraud and cover-up on the nation by claiming that Biden is fit to serve."

BIDEN SURROGATE NEWSOM SAYS CALLS BY FELLOW DEMOCRATS FOR BIDEN TO DROP OUT ‘NOT HELPFUL'

The debate was a major setback for Biden, who at 81 is the oldest president in the nation's history. His halting delivery and stumbling answers at the showdown in Atlanta sparked widespread panic in the Democratic Party and a rising tide of public and private calls from within his own party for him to step aside as its 2024 standard-bearer.

BIDEN TELLS CONGRESSIONAL DEMOCRATS CALLS FOR HIM TO DROP OUT ‘ONLY HELPS TRUMP AND HURTS US’

Over the past week, six House Democrats have publicly called on Biden to end his re-election bid. And on Sunday, Fox News and other news organizations reported that four House Democrats who hold top positions on key committees said on a private conference call that the president needed to step aside.

But the president and his campaign have strongly pushed back against the calls to step aside.

Biden, in a letter sent to congressional Democrats on Monday as they returned from the July 4th holiday recess, reiterated that he's "firmly committed to staying in this race" and argued that "the question of how to move forward has been well-aired for over a week now. And it is time for it to end. We have one job. And that is to beat Donald Trump."

"Any weakening of resolve or lack of clarity about the task ahead only helps Trump and hurts us," the president added. "It is time to come together, move forward as a unified party, and defeat Donald Trump."

WHY TRUMP'S STAYED RELATIVELY QUIET THE PAST WEEK AND A HALF

Over the past week, Trump has kept an uncharacteristically low profile, as his rival for the White House has worked to shore up his campaign.

A source in Trump's political orbit told Fox News a week ago, "How much do we need to do while they are busy committing suicide?" when asked about the campaign's small footprint in the days after the debate.

But Trump is starting to turn up the volume.

Trump called into Fox News' "Hannity" on Monday night for his first TV interview since the debate.

The former president told host Sean Hannity that Biden "may very well stay in" the 2024 presidential race, but said he is prepared if the Democratic incumbent withdraws.

"He's got an ego and he doesn't want to quit," Trump claimed. And If Biden does withdraw, Trump said he would expect to face off against Vice President Kamala Harris.

"I don't think he wants to get out," Trump told Hannity. "But, if he does get out, it will be her."

As Trump heads back out onto the campaign trail – in Florida on Tuesday and in battleground Pennsylvania on Saturday ahead of the Republican convention – a top allied group is also getting into the game.

A super PAC funded in large part by Republican mega-donor Miriam Adelson is set to spend $61 million on TV and digital ads attacking Biden, a source with knowledge confirmed to Fox News.

The commercials from the Preserve America super PAC will begin airing later this month, and are timed to coincide with the start of the Summer Olympics, which is expected to draw massive ratings. The ads will run through Labor Day in Michigan, Pennsylvania and Wisconsin, the three key battleground states known as the Democrats’ blue wall.

The commercials will spotlight the issues of immigration, national security and the economy.

"Joe Biden and his hard-left allies have raised the cost of living, let terrorists cross our border, and crushed our veterans," veteran Republican consultant Dave Carney, a senior adviser for Preserve America, told Fox News. 

"We’re going to put a boot on their necks so he can’t continue ruining our country over the next four years," Carney said.

The Preserve America ad blitz was first reported by Politico.

Fox News' Bryan Llenas contributed to this report

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