For former Republican Ron Filipkowski, the most frustrating moment of Joe Biden’s disastrous debate performance against Donald Trump came in the form of a bizarre exchange about golf.

About one hour and 22 minutes into the verbal sparring match, CNN co-moderator Dana Bash asked the 78-year-old Trump what he would say to voters who have concerns about his capacity to serve as president well into his 80s.

The presumptive Republican nominee began by saying he’d taken - and “aced” - two cognitive tests, before pivoting to his prowess on the golf course.

“I just won two club championships - not even senior,” he boasted, omitting the fact that both championships took place at his own golf club in Florida, and one of them was, in fact, a senior award.

“Two regular club championships! To do that, you have to be quite smart, and you have to be able to hit the ball a long way - and I do. He doesn’t do it. He can’t hit a ball 50 yards. He challenged me to a golf match; he can’t hit a ball 50 yards.”

For Filipkowski - an anti-Trumper who quit the GOP and voted for Biden in 2020 - this was another perfect moment for the president to strike.

He could have shown a sense of humour while pointing out the ridiculousness of Trump’s answer. He could have used it as an opportunity to point out the lies, or contrast its triviality with his own actual achievements in the White House.

“Instead, he starts debating Trump about his golf game, his handicap as vice president, and that he could out-drive him,” says Filipkowski. “I’m like: ‘oh my god’. That moment, to me, summed it all up.”

One day after his shocking performance sparked calls for Biden stand aside, a suddenly energetic president returned to the campaign trail on Friday to assuage supporters that he wasn’t going anywhere.

Gone was the man who struggled to complete sentences the night before. Gone was the sluggish walk, the vacant stare, the raspy voice.

And in its place was shouty, feisty Joe - albeit with a scripted speech and a teleprompter - lashing out at Trump as a serial liar, a threat to democracy, and a ‘one man crime wave’ who would put an end to women’s reproductive rights, slash Medicare, and bow to dictators.

“I know I’m not a young man, to state the obvious,” he told enthusiastic supporters in North Carolina, a swing state that Democrats believe they can win from Republicans in November.

“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 use to. But I know what I do know. I know how to tell the truth! I know right from wrong! And I know how to do this job!”

“When you get knocked down, you get back up!” he added, tapping into a familiar theme as a regular guy from humble beginnings in Scranton, Pennsylvania.

It was the kind of energy and vitality that Democrats had hoped to see the night before, when nearly 48 million viewers tuned in to CNN to watch Biden and Trump make their case for re-election.

The stakes, after all could not have been higher. With five months until Election Day, Biden, who at 81 is America’s oldest ever president, had personally sought a historically early debate with Trump to persuade an increasingly cynical public that he was fit for another four years in the White House.

After all, poll after poll had shown that many voters, including those within his own Democratic ranks, are deeply concerned about his age - even though Trump is only three years younger, and in Biden’s view, “far less competent”.

After one week of prepping with a team of advisers, Thursday night’s stoush in Atlanta was meant to be an opportunity for Biden to also lay out a vision for the next four years in stark contrast to his opponent’s agenda of “revenge and retribution”.

It turned out to be a 90-minute car crash, with Trump’s many lies overshadowed by Biden’s stumbles. Republicans - who have spent months pushing out selectively edited memes portraying the president as a senile old man - were ecstatic.

“As everyone in America saw first hand last night, this election is a choice between strength and weakness, competence and incompetence, peace and prosperity, and war or no war,” Trump said at a rally in Virginia on Friday afternoon, later mocking Biden’s debate prep. “He studied so hard he didn’t know what he was doing.”

As the post-debate dust settled, some of Biden’s staunchest supporters in the party and the press admitted that questions about his ability to run were now unavoidable. Many senior party leaders, however, rallied around the president.

Former Speaker Nancy Pelosi acknowledged that from a “performance standpoint, “Biden’s night “wasn’t great” but added: “from a values’ standpoint, it far outshone the other guy”.

Former President Barack Obama wrote on X that “bad nights happen” - in reference to his own poor debate performance against Mitt Romney in 2012 - but added: “this election is still a choice between someone who has fought for ordinary folks his entire life and someone who only cares about himself”.

And South Carolina congressman James Clyburn, who helped Biden secure the presidential nomination in 2020 by convincing black voters in his state to back him, told reporters that Biden should “stay the course”.

“That was Strike 1. You always get three strikes,” he said.

While some have privately called for Biden to be replaced, party rules make it almost impossible to switch presidential nominees without their consent - particularly a nominee who won 99 per cent of all delegates at the Democratic primaries.

And if Biden were to stand down, who would replace him? Vice president Kamala Harris is theoretically next in line but her approval rating according to polling aggregator Real Clear Politics is currently at 36 per cent - which is less than her boss.

Another top contender is California governor Gavin Newsom - a slick, cut-through politician who was once married to Donald Trump jr’s current girlfriend, Kimberly Guilfoyle, and is now one of Biden’s top surrogates.

But even if Newsom wanted the gig, which he claims he doesn’t while Biden is there, the optics of a white, middle-class man effectively steamrolling America’s first black female vice president would enrage a large section of the Democratic Party.

“Kamala Harris is not just going to bow out, and a big chunk of the Democratic base is very loyal and very enthusiastic to Kamala,” said one insider.

“So if you do something that infuriates her or alienates her, those voters may not show - and that’s a problem.”

Asked if the party had a Plan B, Democratic strategist Antjuan Seawright told this masthead that there is no need for one yet because Plan A remains solid.

“Joe Biden did not have the best night, but he did not have the worst night,” he says.

“Remember, Barack Obama had a bad debate performance in 2012 and he won the election. Hillary Clinton had a great performance in 2016 and she lost. One debate does not define everything.”

Biden is banking on it.

“I would not be running again if I didn’t believe with all my heart and soul I can do this job,” he told the crowd in North Carolina on Friday. “Because, quite frankly, the stakes are too high.”

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