Joe Biden is digging his heels in. “I’m not going anywhere,” the president said in a Monday call-in appearance on MSNBC’s Morning Joe, just after sending a letter to elected Democrats rejecting the mounting pressure to drop his reelection bid and make way for a younger candidate. “I wouldn’t be running again if I did not absolutely believe I was the best person to beat Donald Trump in 2024,” the letter read. “Any weakening of resolve or lack of clarity about the task ahead only helps Trump and hurts us.”

“It is time to come together, move forward as a party, and defeat Donald Trump,” he added.

The message to Democrats, as former Obama strategist David Axelrod put it Monday, is simple: “Save your breath and get on board." But it remains to see if it convinces anyone to drop concerns about the viability of his candidacy: With the Morning Joe spot, the president at least seems to be heeding guidance from prominent Democrats to get out of his scripted environment in an effort to “do the things necessary to restore voters’ confidence or answer voters’ questions,” as Democratic Senator Chris Murphy urged him to do in a Sunday appearance on CNN. “I think the president needs to do more.” On the other hand, both the letter to Capitol Hill Democrats and the friendly interview with Joe Scarborough and Mika Brzezinski—in which he railed against party “elites,” a rank that somehow doesn’t include himself as president, former vice president, and longtime senator—demonstrated the type of defiance that has been nearly as worrying as the dreadful debate performance that touched off this panic in the first place.

Indeed, the White House and the Biden campaign have repeatedly brushed off concerns about his ability to once again beat Trump, casting those calling for him to step aside as “bedwetters,” dismissing polls that consistently show him losing even more ground to his demagogic rival, and accusing the media of blowing the story of his bad “90 minutes on stage” out of proportion while ignoring his accomplishments over three and a half years of his presidency. Those three and a half years have yielded impressive progress on a number of fronts, and he and the Democrats have defied expectations before. But that doesn’t mean the streak will necessarily continue, and his displays of confidence in the days since the debate have at times seemed blasé about the stakes of the election.

“If you stay in and Trump is elected and everything you’re warning about comes to pass,” George Stephanopoulos asked Biden in a primetime ABC News interview aired Friday evening, referring to the president’s correct assessment of his Republican opponent as a threat to democracy, “how will you feel in January?”

“I’ll feel, as long as I gave it my all and I did the good as job"—or was it “goodest job?”—"as I know I can do, that's what this is about," Biden replied.

That was an insufficient answer, to say the least: “This is not just about whether he gave it the best college try, but rather whether he made the right decision to run or pass the torch,” as Democratic Representative Adam Schiff put it Sunday. “That is the most important decision for him to make right now.” Asked about that criticism by Scarborough Monday, Biden chuckled: “I haven’t lost,” he said. “I beat [Trump] last time. I’ll beat him this time.”

Plenty within the party remain unconvinced: Four senior House Democrats—Jerry Nadler, Adam Smith, Joe Morelle, and Mark Takano—have joined the chorus of voices encouraging him to leave the race, and several others, including Jamie Raskin, have expressed skepticism about his current path to reelection. And while a Monday meeting about Biden’s candidacy, to be headed by Senator Mark Warner, was apparently scrapped after word of it got out, the pressure could continue to build around him. “People have to act,” Representative Mike Quigley, who is among the Democrats who have asked Biden to step aside, told Politico, urging the party to show Biden “tough love.”

“It’s pretty clear that he’s not going anywhere unless there’s a major revolt on the Hill,” as a senior Democratic National Committee staffer put it to Reuters.

It’s unclear still if top Democrats—some of whom have remained publicly supportive of the president—will stage one, especially with Biden refusing to budge. “I don’t think what those big names think,” Biden told Morning Joe. “I am not letting up.” But it isn’t just party or media “elites” in Washington behind all this pressure; three-quarters of respondents in a CNN poll after the debate meltdown last month said the party would stand a better chance of defeating Trump with a different Democrat at the top of the ticket, a finding supported by other surveys, as Jon Favreau pointed out: “This is not an elite thing. The voters have been voicing these concerns for months now. Denying them or dismissing them is not the way to overcome them.”

The trouble for Biden, of course, is that the biggest issue haunting his campaign is one that can only be kept in check, but not fully fixed. True, the fact of his age pales in comparison to the extraordinary danger and extremism of his opponent, a twice-impeached convicted felon whose own performance in the June debate should’ve served as a reminder of his corruption, incompetence, and mendacity. But the question Democrats need to answer—and soon—is if there is someone else in their ranks who might actually be able to better make all that the focus of this race. “Given Biden’s incredible record and given Trump’s terrible record, he should be mopping the floor with Donald Trump,” as Schiff noted. “It should not even be close, and the reason it is close is the president’s age.”