CNN  —  On MSNBC, the mood Thursday night was somber. “I am not going to put a fine sheen on it, or a spin on it, even though I am in the spin room,” MSNBC anchor Alex Wagner said from the CNN presidential debate spin room in Atlanta. “There has been a uniformly negative reaction to Biden’s performance tonight.” Wagner was speaking about the reaction from Democratic sources, but on the cable news channel that’s seen as the home to America’s progressive political wing, the mood on set was stark. “This was about revealing who Donald Trump was, but it was also Joe Biden battling a caricature of himself as an enfeebled person,” Wagner said of the debate. “And he did nothing to disabuse, I think, the country of the notion that he is very old and was lost frequently in that debate.” While the Democratic party immediately declared victory following President Joe Biden’s debate with former President Donald Trump, Biden’s poor performance on the CNN stage, in which the 81-year-old spoke in a hoarse and at-times unintelligible voice as Trump unleashed a flurry of lies, set off alarm bells on the left. “It’s kind of a DEFCON 1 moment,” David Plouffe, former President Barack Obama’s campaign manager, told MSNBC star Rachel Maddow following the debate. “It really pains me to say this — they are about three years apart, they seemed like 30 years apart tonight.” The concerns didn’t end there. MSNBC host Joy Reid told viewers she was receiving messages from Democratic sources expressing anxiety about the president’s performance, prompting an open discussion of a once-unspoken idea: replacing Biden as the party’s nominee. “The universal reaction was somewhere approaching panic. The people who were texting with me were very concerned about President Biden seeming extremely feeble, seeming extremely weak,” Reid said. “I think conversations range from whether he should be in this race tomorrow morning to what was wrong with him,” anchor Nicolle Wallace said. “There were people talking about how that process works, and that conversation is live and active at the highest levels of the Democratic party.” “Someone actually sent me the rules,” Reid said, referring to the Democratic Party’s nomination rules. “The rules are circulating!” Wallace replied. The anxieties relayed on the progressive outlet Thursday night came in sharp contrast to right-wing media’s reaction to Trump’s history of scandals and lies. During and after Trump’s time in the White House, prominent figures on Fox News and other right-wing outlets vigorously defended the Republican in the face of two impeachments, the January 6 attack, a felony conviction and the reality that he lost the 2020 election. And while MSNBC’s hosts pointed to the flood of lies from Trump during Thursday night’s debate, the conversation continually returned to Biden’s performance. “The president is an avatar for the American people,” Reid said, offering support for Biden’s record as president. “But you cannot become president again when America looks at you and that avatar to them looks broken.” “The job of the president is making decisions. The job of a presidential candidate is to communicate. It just is. That is the job,” MSNBC anchor Chris Hayes later added. “I think Joe Biden has a very good record on making decisions. And I think he is a very poor communicator right now.” Outside the MSNBC studio, other prominent liberal voices suggested Biden should step aside following the debate. “President Biden is a good man who capped a long career in public service with a successful presidential term. But I hope he reviews his debate performance Thursday evening and withdraws from the race, throwing the choice of a Democratic nominee to the convention in August,” New York Times columnist Nicholas Kristof wrote. “Joe Biden had his shot—a chance to dispel concerns about his age and his abilities,” David Corn wrote in Mother Jones, the progressive website and print magazine. “But in his first debate with Donald Trump, he stumbled through 90 minutes, muffing answers, often looking uncertain, speaking in a low, gravelly voice that did not convey strength. This was not only a missed chance. It was a disaster.” Mehdi Hasan, the Zeteo editor-in-chief and former MSNBC anchor, struck a similar chord. “Joe Biden’s got to go,” Hasan said. “Tonight was a car crash for the Biden presidency, for the Biden campaign. It was painful to watch at times, I’m sorry, it felt like elder abuse.” But while some were calling for Biden to step aside, others urged patience with the candidate as the campaign revved up to the November election. “Predictably, Biden’s poor performance led to some chatter about his stepping down and letting someone else be the nominee. This is not going to happen,” MSNBC host Symone Sanders, who advised then-candidate Biden ahead of the 2020 election, wrote early Friday. “It’s tight, but Biden still has time to make his case. After all, presidential campaigns are about fighting all the way until the end.”