1 hour agoBy Katty Kay, @KattyKay_, US Special CorrespondentReutersJoe Biden’s surprisingly bad debate performance on Thursday night has prompted panic, confusion and even sadness in the Democratic Party, including among people close to the president.There are now serious conversations taking place at the top of the party, in the White House and in the Biden-Harris campaign about a range of options, one of which is whether Joe Biden should step down as a candidate for president.Democratic officials, political operatives, and people close to the president paint a picture of an anxious Democratic Party that is seriously concerned about the strength of their candidate and whether he can beat Donald Trump in November.Among some of the president’s allies I’ve spoken to, there’s been hand-wringing about how the preparation for the debate in Atlanta was handled.These people say Mr Biden was over-prepared and overworked by his campaign team – and that if he had been given more time simply to rest in the week leading up to the debate, he would have done much better. Maybe there were too many voices and perspectives and data points put in his head, one campaign source suggested to me, and that just threw him off.While that analysis may be correct, the claim that the president was tired and overworked will do little to quell the very real fears that Mr Biden’s advanced age may impact his ability to win this election.These fears over the president’s age, mental fitness and stamina – and the insistence that something must be done about it – are far from new.Back in September, the prominent political columnist David Ignatius, who was a confidant of Mr Biden’s, stated that the president should step aside. In February, Ezra Klein of the New York Times said much the same in a column that generated both buzz and irritation among those inside the White House.Until now, those voices have been one-offs. That changed after last night’s poor debate performance.Name-calling and insults – key moments from Biden and Trump’s debateIn the early hours of Friday morning, a string of high-profile Democratic strategists, pundits, and former officials joined the call for Mr. Biden to bow out. I appeared on Morning Joe, an American political morning show that the president frequently watches. Joe Scarborough, the host of the program and a defender of the president, made the point that while Mr Biden can still govern the country, perhaps he no longer has what it takes to win the election.So where does that leave Joe Biden?First, it is important to remember that the decision of whether to continue is – more or less – entirely his. At this point, if he doesn’t want to step back, it’s virtually impossible for him to be removed from the ticket. One campaign source told me any decision to step down would be made by a very small group that includes the president, his wife and his sister, Val Biden.Second, right now the conversation about whether to replace Mr Biden is happening in public among pundits and former officials but it’s still only happening in private among those with actual influence.Indeed this morning, several of the president’s allies (who are also, awkwardly, being floated as his potential replacements) took to television and social media to defend him.California Governor Gavin Newsom said he was “very proud of the president”. Pennsylvania Governor Josh Shapiro told Democrats to “stop worrying”. Senator John Fetterman put it bluntly, saying: “I refuse to join the Democratic vultures on Biden’s shoulder.”My reporting suggests no changes will be made imminently. The team wants to give the president a chance to get out in public and erase the memory of that debate appearance. He has rallies and public events where they say he will be strong and vigorous.On Saturday, Mr Biden will travel to the ultra-wealthy Hamptons region of New York for fundraisers with Democratic donors.A source on the campaign tells me that, at the moment, the chance of him stepping aside is only around 5%. But if donors were to abandon him en masse, they acknowledge that could change and prompt a speedier decision about his candidacy.Polling on the public’s reaction to the debate should filter in over the next few days. That too will guide the discussions.Already the campaign is pointing to snap polling data from the debate that shows independent voters had a more unfavourable response to Donald Trump than to Joe Biden. They hope that is replicated in later polls.Joe Biden has been discounted many times before in his political career. When he first ran for Senate he was told he was too young. When he thought of running for president in 2016 he was told it wasn’t his turn. And in 2020 many people felt he didn’t represent the future of a diverse Democratic Party.He has developed a habit of ignoring sceptics. The only people he really trusts are the few close advisers who’ve been with him for years. I’ve been told those advisers, including Ron Klain and Mike Donilon (who prepared him for this disastrous debate), also happen to believe that Joe Biden is the only person who can beat Donald Trump.They were right in 2020. Are they still right today?Yes, Joe Biden has a history of bouncing back, but many Democrats are worried this time is different.