President Joe Biden admitted “I don't debate as well as I used to” but said “I know how to do this job” as he appeared at a rally in North Carolina on Friday.
It follows his “disastrous” TV debate against Donald Trump on Thursday night, which fuelled concerns from even members of his own party that at age 81 he's not up for the task of leading the country for another four years.
Thursday night's faceoff appeared to reinforce the US public's deep-seated concerns about his age.
It was leapt on by his opponent with the Republican nominee saying he had won a “big victory” against Biden.
Speaking at a rally in Virginia, Mr Trump poked fun at the President saying he "studied so hard" before the debate he "didn't know what he was doing".
He told his supporters Mr Biden was "grossly incompetent", saying he was "not respected" around the world and was causing the US to be "laughed at".
But former US president Barack Obama came out in defence of Mr Biden on Friday, writing on X, formerly Twitter: “Bad debate nights happen. Trust me, I know. But this election is still a choice between someone who has fought for ordinary folks his entire life and someone who only cares about himself.
“Between someone who tells the truth; who knows right from wrong and will give it to the American people straight — and someone who lies through his teeth for his own benefit.
“Last night didn’t change that, and it’s why so much is at stake in November.”
Bad debate nights happen. Trust me, I know. But this election is still a choice between someone who has fought for ordinary folks his entire life and someone who only cares about himself. Between someone who tells the truth; who knows right from wrong and will give it to the…
— Barack Obama (@BarackObama) June 28, 2024
On Friday supporters in North Carolina were animated as they cheered, clapped and chanted “four more years” as Mr Biden spoke on healthcare, crime and standing up to Putin.
“America bows to no one, no one ever,” he said.
Speaking for 18 minutes, Mr Biden repeatedly appeared far more animated than his showing the night before, and he excoriated Mr Trump for his "lies" and campaign aimed at "revenge and retribution."
Joe Biden: 'I don't walk as easy as I used to, I don't speak as smoothly as I used to, I don't debate as well as I used to, but I know what I do know... I know how to tell the truth'
— Sky News (@SkyNews) June 28, 2024
He adds: 'When you get knocked down you get back up'
Latest: https://t.co/EK9F4N20ac pic.twitter.com/o82rQ7M83Y
"The choice in this election is simple," he said. "Donald Trump will destroy our democracy. I will defend it."
Commentators said Mr Biden’s performance was better on Friday because he was using a teleprompter to deliver his speech - something he did not have for the CNN debate.
Democrats on Friday acknowledged Mr Biden's poor performance, but tried to stop talk of replacing him as their standard-bearer.
"Well, the president didn't have a good night, but neither did Donald Trump with lie after lie and his dark vision for America," North Carolina Gov. Roy Cooper told The Associated Press.
"We cannot send Donald Trump back to the White House. He's an existential threat to our nation."
Rep. Ritchie Torres, Democrat of New York, said, "Since performance last night, I had to take a few more antidepressants than usual."
"People have asked me, 'Do I feel comfortable with the debate?' You know, a Donald Trump presidency would cause me far greater discomfort than a Joe Biden debate performance."
Mr Biden was greeted early Friday in Raleigh by throngs of supporters invited by his campaign to watch Air Force One carry him from the debate in Atlanta, where he brushed aside Democratic concerns with his showing that he should consider stepping aside, saying, "No, it's hard to debate a liar."
The Democrat will travel to New York for a weekend of big-dollar fundraisers that his campaign now needs more than ever, as it looks to stave off Trump.
Mr Biden's campaign announced that it raised $14 million on debate day and the morning after, while Mr Trump's campaign said it raised more than $8 million from the start of the debate through the end of the night.
Vice President Kamala Harris, whom the Biden campaign sent out to defend his performance, was set to travel to Las Vegas, Nevada. She told CNN hours after the debate, "There was a slow start, but it was a strong finish."
Rep. Emanuel Cleaver, D-Mo., said he could hardly sleep because of the number of telephone calls he got after Biden performed "horribly" in the debate.
"People were just concerned. And I told everybody being concerned is healthy, overreacting is dangerous," Cleaver said. "And I think I wouldn't advise anybody to make rash decisions right now."
Rep. James Clyburn, a South Carolina Democrat who was formerly a longtime fixture in House Democratic leadership, said he would likely speak to Biden later Friday and his message would be simple: "Stay the course."
Mr Trump's comments, Mr Biden's team insisted, are out of step with the majority of voters and will serve as fodder for the barrage of ads that they will see through Election Day.
Michigan Gov. Gretchen Whitmer, a Democrat frequently mentioned as a 2028 contender and speculated about as a potential replacement for Biden on the ticket should he step aside, released a statement backing him on Friday.
"The difference between Joe Biden's vision for making sure everyone in America has a fair shot and Donald Trump's dangerous, self-serving plans will only get sharper as we head toward November," she said.
California Gov. Gavin Newsom also dismissed questions on whether he would consider stepping in for Biden, telling reporters after the debate, "I will never turn my back on him."
Under current Democratic Party rules, it would be difficult, if not impossible, to replace Biden as the party's nominee without his cooperation or without party officials being willing to rewrite the rules at the August national convention.
Democratic National Committee Chairman Jaime Harrison tried Friday to tamp down concerns.
"He beat him once. He'll beat him again," Harrison said in Atlanta when asked whether the president was his party's best nominee against Trump. "One of the things that notoriously Democrats are known for, some of us like to wring our hands," Harrison said. "It's not time to wring hands. It's about rolling your sleeves to do the work."
Trump, meanwhile, flew to his golf club in Virginia, a onetime battleground that has shifted toward Democrats in recent years but that his aides believe can flip toward the Republican in November. He was set to hold at rally in Chesapeake Friday afternoon.
