The contest was seen as a test of each man's fitness for office.
In a historic clash of personality and policy, Joe Biden and Donald Trump took the stage for the first presidential debate of the 2024 election.
The showdown provided a rare opportunity for both candidates to move the needle in what has been a stubbornly tight race for the White House, but at the end of the night, Biden's halting performance raised new concerns among Democrats and cause Republicans to celebrate.
The debate was a rematch for Biden and Trump, who faced each other twice in 2020, but a first-of-its-kind format and a vastly different political landscape presented new challenges for the two rivals.
An hour in and here is the Biden campaign spin on what so far has been a rocky performance by the president.
Biden has a cold (but tested negative for COVID-19), the campaign confirms. They haven't offered any explanation for why they didn't disclose this sooner.
Overall, the campaign says they are feeling fine. They agree it was a slow start but say he's found his groove.
-ABC News' Mary Bruce and Molly Nagle
Trump has made several comments about going after his political opponents and retribution. Asked to clarify what he meant, Trump replied, "Well, I said my retribution is going to be success."
He also contended that he's done nothing wrong despite his numerous criminal and civil cases.
Biden fired back contending that Trump's claims that he has the right to seek retribution is wrong. He then went after Trump over his various scandals.
"The crimes you are still charged with and think of all the civil penalties you have, how many billions of dollars ... and civil penalties? For molesting a woman in public for doing a whole range of things ... having sex with a porn star ... while your wife was pregnant? What would you be talking about? You have the morals of an alley cat," Biden said.
After a stifled and stumbling opening statement, Biden has had some good replies to Trump when talking about policy -- especially on abortion and Jan. 6. But that will be little comfort for his campaign, which is fighting hard against the impression that Biden is too old to hold office. In a 538/Ipsos poll of Americans released today, 40% of Americans said they rated Biden's mental fitness to be president as "terrible," compared to 35% for Trump -- and fewer Americans rate him positively for his physical fitness to lead, too.
538's election forecasting model currently gives Biden and Trump each a 50-in-100 chance of winning the election. Biden's initial impression could prevent him from making sizable gains over those numbers, despite the rest of his performance.
-538's G. Elliott Morris
When asked point-blank whether he believes the millions of Americans who are likely to vote for Trump will be voting against American democracy -- in reference to the president's past comment that Trump and his MAGA Republicans are "determined to destroy American democracy," Biden responded, "Yes, the more they know about what he's done."
Biden went on to reference Trump's comment that there were "very fine people on both sides" of clashes at a white supremacist rally in Charlottesville, Virginia, in 2017.
"This guy has no sense of American democracy," Biden said.
Trump called his accusation false.
