Biden acknowledges debate performance: 'I know how to do this job'

President Joe Biden "doesn’t debate as well" as he used to, he said in a fiery campaign speech Friday, but he adamantly told supporters he knows "how to tell the truth" and "how to do this job."

Biden made the comments at a rally in Raleigh, North Carolina, a day after his lackluster debate performance against Donald Trump prompted concerns within his own party that the 81-year-old Democrat is not up to the task of being commander-in-chief.

Biden's delivery was halted and he appeared to lose his train of thought throughout the debate. His raspy, whispering voice left many viewers wondering if the president was sick; Biden’s campaign said he’s getting over a cold. 

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Trump, though his comments were mostly false and provocative, appeared more confident and vigorous than Biden. Polls show the majority of viewers believe Trump won the debate

The president acknowledged the debate performance Friday, but appeared far more animated than he did on television the night before. 

President Joe Biden gives speech during campaign rally in Raleigh, North Carolina on June 28, 2024. (Credit: Getty Images)

"I know I’m not a young man, to state the obvious … 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," Biden said at the rally. "I know right from wrong. And I know how to do this job. I know how to get things done. And I know, like millions of Americans know, when you get knocked down you get back up."

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Before the rally, his campaign had spent the previous hours working to tamp down concerns and keep donors and surrogates on board. 

Democratic lawmakers on Friday also admitted that Biden had a "bad night," but they haven’t called for him to step aside and be replaced with another nominee. 

Biden's campaign says it raised $14 million on debate day and the morning after, while Trump's campaign says it raised more than $8 million from the start of the debate through the end of the night.

"Donald Trump is a threat to everything America stands for," Biden said in his North Carolina speech. "The choice in this election is simple. Donald Trump will destroy our democracy. I will defend it."

The Associated Press contributed to this report.