Former President Barack Obama offered public support for President Joe Biden after a rough debate performance Thursday that spurred some Democrats to question whether the incumbent has what it takes to defeat Donald Trump.

“Bad debate nights happen. Trust me, I know,” Obama said in a post on X, a reference to his own first debate with 2012 GOP nominee Mitt Romney, which was widely viewed as a victory for the Republican.

But the former president pointed to bigger contrasts between Biden and Trump, echoing a strategy other Democrats have made since Thursday’s debate.

“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,” Obama said. “Last night didn’t change that, and it’s why so much is at stake in November.”

Prominent Democrats have moved quickly Friday to rally behind Biden after a disastrous debate that saw Biden stumble over his words in key moments and fail to articulate key differences from Trump, even on issues such as a abortion rights that should favor his party. Influential Rep. Jim Clyburn (D-S.C.) said Friday morning that he would tell Biden to “stay the course.”

That is unlikely to fully quell the panic that has spread across Democrats, who expressed during and immediately after the debate that Biden had done nothing to alleviate voter worries about his age.

Before the debate had even ended, some Democratic strategists and donors were already contemplating how Biden could be replaced at the top of the ticket. Friday morning, a handful of liberal columnists joined the calls for Biden to step aside.

Some congressional Democrats on Friday said they would rather not see Biden debate again after the performance, though they did not call for the party to replace him as its nominee.

Biden acknowledged the challenge at a Friday rally too, saying he does not debate as well as he used to, but that he knows “how to do this job.”