Barack Obama is sticking by his former vice president.

After President Joe Biden’s floundering debate performance Thursday night threw the Democratic Party into a state of panic, Obama, who was president from 2009 to 2017, chimed in with a message of support.

“Bad debate nights happen. Trust me, I know,” he wrote on social media.

“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,” Obama went on. “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.”

“Last night didn’t change that, and it’s why so much is at stake in November,” he concluded, dropping a link to Biden’s campaign website.

Obama has already helped Biden, the presumptive Democratic nominee, raise millions of dollars for reelection, most recently with a glitzy, celebrity-packed Los Angeles fundraiser.

Obama himself suffered a memorable defeat in his first debate of the 2012 presidential cycle with former Massachusetts Gov. Mitt Romney. On stage in Denver, Obama appeared tired, sluggish and even irritable, leading The Washington Post to wonder: “Why was President Obama so bad?”

The then-incumbent Obama was able to find his footing in subsequent debates and won a second term that year with Biden as vice president.

But the concerns surrounding Biden’s present candidacy have to do with the immutable fact of his age.

Former President Donald Trump lied and evaded his way through the debate, but still managed to sound crisp and concise in comparison to Biden, whom Trump is only three years younger than.

The debate has some Democratic strategists asking whether Biden should be replaced as the party’s nominee during the convention in late August.

Biden himself acknowledged the criticisms on stage at an event Friday afternoon — where he sounded markedly more energetic.

“I know I’m not a young man,” Biden told a spirited crowd. “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 used to, but I know what I do know: I know how to tell the truth. I know right from wrong. I know how to do this job. I know how to get things done. I know, like many of Americans know, when you get knocked down, you get back up.”