Biden Back On Campaign Trail As Pressure Mounts

US President Joe Biden was back out on the campaign trail Sunday, desperate to salvage his reelection bid as senior Democrats meet to discuss growing calls that he quit the White House race.

The 81-year-old Democrat kicks off a grueling week with two campaign events in the battleground state of Pennsylvania, before hosting the NATO leaders' summit in Washington.

He will do so under an increasingly unforgiving spotlight, as pressure mounts for him to drop out after his disastrous debate against Donald Trump last month ignited panic over his age and fitness to serve another four years.

Biden has remained defiant, unequivocally declaring -- at a rally, to reporters and on social media -- that he is fit to serve, the only one who can defeat Trump, and staying in the race.

"I beat Trump in 2020. I'm going to beat him again in 2024," his campaign social media account posted Saturday.

But a televised interview with ABC News on Friday has failed to quell concerns. His next major test in the public eye after Sunday's forays will be a press conference scheduled for Thursday, during the NATO summit.

So far, five Democratic lawmakers have called on Biden to drop out, with the drumbeat of dissent slowly rising.

Democratic Senator Chris Murphy, a close Biden ally, stressed he believes Biden can still recover and win. But he said "the president needs to do more," including unscripted events like town hall gatherings, to reassure voters he has the mental acuity and physical fitness for a second term.

"I think this week is going to be absolutely critical," Murphy told CNN's Sunday talk show "State of the Union," adding he believes there are many voters who need to be convinced of Biden's capabilities.

"If he can't do that, then of course he's going to have to make a decision about what's best for the country."

Those comments came as House Minority Leader Hakeem Jeffries has scheduled a virtual meeting of senior Democratic representatives for Sunday to discuss the best way forward, and Democratic Senator Mark Warner is reportedly working to convene a similar forum in the upper chamber.

First Lady Jill Biden, who -- according to some US media reports -- is urging her husband to stay in the race, is scheduled to campaign for him Monday in Georgia, Florida and North Carolina.

But after Sunday's stops in Philadelphia and Harrisburg, the president will have to step away from the trail for the NATO summit beginning Tuesday.

Here, too, he will find himself having to reassure allies at a time when many European countries fear a Trump victory in November.

The 78-year-old Republican has long criticized the transatlantic defense alliance as an unfair burden on the United States, voiced admiration for Russian strongman Vladimir Putin, and insisted he could bring about a quick end to the fighting in Ukraine, where Moscow's invasion is in its third year.

For now, Democratic heavyweights are largely keeping a lid on any simmering discontent with their leader -- at least in public.

But with election day just four months away, any move to replace Biden as the nominee would need to be made sooner rather than later, and the party will be scrutinized for any signs of more open rebellion.

Meanwhile, for Biden and his team, the strategy seems to be to ride it out.

The campaign has unveiled an intense battle plan for July, including an avalanche of TV spots and trips to all the key states.

That includes a visit to the US Southwest during the Republican convention July 15-18, at which Trump is set to be anointed the party's official presidential nominee.

In what had been billed as a make-or-break Friday interview with ABC News, Biden flatly dismissed his falling poll numbers and concerns over his fitness triggered by his dismal June 27 performance against Trump.

But some of his answers were tentative or meandering, even as he deflected questions about his mental acuity and dismissed the notion his party would consider replacing him.

"If the Lord Almighty came down and said, 'Joe, get out of the race,' I'd get out of the race," he said.

"But the Lord Almighty is not coming down."