Members of President Biden’s own re-election effort think he has no chance of defeating Republican Donald Trump following last month’s debate debacle — and have been quietly polling Vice President Kamala Harris in the ticket’s top spot should the 81-year-old step aside.

“He needs to drop out,” one Biden campaign official told NBC News of the president. “He will never recover from this.”

“No one involved in the effort thinks he has a path,” another source told the outlet.

The internal surveys, reported by the New York Times, pitting Harris, 59, against the 78-year-old Trump likely serve one of two purposes, according to Democratic pollster John Zogby, founder of an eponymous marketing and political consulting firm. 

Either Harris “does worse, and [shows] that Biden has a reason to stay in the race,” he said, or, “more than likely, they’re testing to see if he can hand the reins of the campaign over to her.”

Meanwhile, Democrats on Capitol Hill are biding their time until after this week’s NATO summit to pressure Biden into ending his re-election bid — as prominent lawmakers teased that more of their colleagues would soon come out against the commander-in-chief.

“I’m of the belief that this is very close to the end,” Zogby told The Post.

“[I think] that the NATO summit wasn’t a test so much for Biden as it was a holding action,” he added. “You don’t embarrass the world’s leader in front of world leaders. You’re going to see more and more Congresspeople come out and I think the end is very near.”

The scale of the bad feeling between Congress and the White House became clear at lunchtime Thursday, when senior Biden advisers Mike Donilon and Steve Ricchetti and campaign co-chair Jen O’Malley Dillon met with Senate Democrats — including Majority Leader Chuck Schumer of New York and President Pro Tempore Patty Murray of Washington — at their main campaign arm’s headquarters on Capitol Hill.

A senior Capitol Hill aide told The Post that the meeting was a two-way vent session, with senators sharing how they were “displeased” with White House and campaign officials working so hard to “insulate” the president from the public through highly structured meetings and appearances.

The Biden advisers shared some “sour notes” about the state of the campaign with lawmakers, the aide said, but for the most part, maintained a positive outlook — apparently “in denial” about the president’s chances.

Neither Schumer nor Murray took questions from the press, but other Democrats facing no immediate threat to their seats defended the party’s leader.

“The President’s team made a very strong presentation, and I continue to support the re-election of President Biden,” said Maggie Hassan of New Hampshire, who is not up for re-election until 2028.

Richard Blumenthal of Connecticut, another member of the class of 2028, was less bullish on Biden, telling reporters he wanted “more data, more analytics” about the incumbent’s path to defeating Trump.

“Some of my concerns are allayed, some others have been deepened,” he said.

Michael Bennet of Colorado, who predicted earlier this week that Biden will lose “by a landslide” on current form, told reporters before the meeting that calling for the president to withdraw was “not a decision for me to make.”

Bennet departed the meeting about two hours later with a grim expression and declined to take questions.

So far, 12 congressional Democrats have already publicly called on Biden to step away from the 2024 race, but more have hinted at their distress with the course of the incumbent’s campaign, particularly following his disastrous debate against Trump on June 27.

“I think everyone will be talking over Friday, Saturday and by Sunday you should have some idea of what’s going on,” Sen. Joe Manchin (I-WV) told reporters Thursday on his way into the lunch meeting with Donilon, Ricchetti and O’Malley Dillon.

Manchin, who is leaving Congress early next year, reportedly had to be talked out of publicly breaking with Biden during an appearance on a Sunday morning public affairs program following the debate, at which Biden frequently appeared confused and frail.

What to know about the calls for President Biden to drop out of the 2024 race:

• President Biden’s poor performance in the first 2024 presidential debate left some Democrats unsure of his fitness for office and future as the party’s candidate.
• More than a dozen congressional Democrats have joined in calling for Biden’s exit from the race. Former Biden supporter George Clooney echoed these calls in an op-ed published in the New York Times just weeks after he helped lead a record-breaking fundraiser for the Democrat.
• Democratic voters have continued to raise concerns about Biden’s nomination since the debate, with speculations and suggestions for replacement nominees running rampant.
• Biden’s former running mate Barack Obama has reportedly been trying to pressure him to drop out, and had prior knowledge of Clooney’s op-ed. Former House Speaker Nancy Pelosi allegedly told Biden he could not beat former President Donald Trump this time around.
• As the Democratic National Convention approaches, California delegates for the Democratic Party are reportedly in disarray as debate over the president’s chances of re-election threatens to tear the party apart.
• However, the Biden campaign has denied any plans for Biden to bow out and for Kamala Harris to step in as the Democratic nominee. Sources close to the president believe he might not be willing to drop out, while other sources claim he is “receptive” to giving up on a second term.

The strongest suggestion that Biden’s fate would be sealed after the gathering of NATO heads of government in the nation’s capital came from former House Speaker Nancy Pelosi (D-Calif.), who told MSNBC’s “Morning Joe” that Democrats were “all encouraging him to make that decision because time is running short.”

Apparently ignoring Biden’s stated desire earlier this week to remain in the race, the 84-year-old Pelosi added that “I want him to do whatever he decides to do. And that’s the way it is. Whatever he decides, we go with. I think it’s really important and I would hope everyone would join in.

“Let him deal with this NATO conference,” Pelosi said. “This is a very big deal. Thirty heads of — over 30 heads of state are here. He is the host of it, and that means not just hosting, it means orchestrating the discussion and setting the agenda. And he’s doing so magnificently. And I’ve said to everyone, let’s just hold off whatever you’re thinking. Either tell somebody privately, but you don’t have to put that out on the table until we see how we go this week.”

On Thursday, Politico reported that Pelosi’s comments were meant as a “subtle green light” for Democrats — particularly those in battleground districts — to speak out if they want Biden off the party’s ticket.

The NATO summit was scheduled to be capped by an evening press conference featuring Biden, which one Democratic operative called “another make or break moment” for the octogenarian.

“I feel like the narrative needs to change,” this person said. “So either Dems need to get behind Biden or he needs to step aside. But we are losing time.”

House Minority Leader Hakeem Jeffries (D-NY) played coy about the Biden situation Thursday, saying that his conference was “engaged in a process of talking to each other” and declining to comment about pressure from donors or other outside stakeholders

Jeffries also denied that he’s worried that Biden could become a liability for his most vulnerable members.

Meanwhile, multiple reports indicated Thursday that doubts about the president have spread to members of his own campaign team — who have begun quietly conducting surveys pitting Vice President Kamala Harris against Trump, the presumptive Republican nominee, the New York Times reported.

“He needs to drop out,” one Biden campaign official told NBC News. “He will never recover from this.”

“No one involved in the effort thinks he has a path,” another source told the outlet.

Zogby suggested that polling Harris against Trump would serve two separate purposes: Either “she does worse, and that Biden has a reason to stay in the race,” or, “more than likely, they’re testing to see if he can hand the reins of the campaign over to her.”

Shortly after the debate, Biden deputy campaign manager Rob Flaherty sent out a fundraising blast bashing the “bedwetting brigade” of Democrats who want Biden to step aside.

He attached polling from left-wing shop Data for Progress that showed Biden and Harris faring better against Trump than other pretenders, such as California Gov. Gavin Newsom and Michigan Gov. Gretchen Whitmer.

“The question for me, and a lot of us, is: Who is the best person to beat Donald Trump?” another individual described as working to re-elect Biden told NBC News. “There are a lot of us that are true blue that are questioning our initial thoughts on that.”

Let's break down Clooney's role in Biden's 2024 presidential campaign

• George Clooney has played a role in Democratic fundraising since Barack Obama’s 2012 run, including leading a benefit for former Vice President Joe Biden in 2020 and another in June 2024.
• Clooney, joined by actresses Julia Roberts and Barbra Streisand, helped Biden take in a record $30 million-plus at a star-studded fundraising event in New York City just last month.
• Just weeks later, Clooney turned on Biden and published an op-ed in the New York Times calling for the 81-year-old to leave the race following his atrocious debate appearance.
• Clooney wrote that Biden “cannot win” in November, adding that the president is not the man he used to know, but rather “the same man we all witnessed at the debate.” The actor even said that “every senator and Congress member and governor that I’ve spoken with in private” agrees that Biden must step down.
• Donald Trump blasted Clooney for his comments, telling him to “get out of politics and go back to TV,” and said the actor had “turned on Crooked Joe like the rats they both are.”
• A report also revealed that Obama knew ahead of time what Clooney planned to write and did not object to the op-ed.

Campaign manager Julie Chavez Rodriguez and campaign chair Jennifer O’Malley Dillon argued in a memo sent to their team Thursday that there is a “clear pathway ahead for us,” the New York Times reported.

“There is also no indication that anyone else would outperform the president vs. Trump,” they went on.

“Hypothetical polling of alternative nominees will always be unreliable, and surveys do not take into account the negative media environment that any Democratic nominee will encounter. The only Democratic candidate for whom this is already baked in is President Biden.”

The Biden campaign did not immediately respond to an inquiry from The Post.