 ABC News, I'm Sherry Preston. President Biden doubling down on his decision to stay in the presidential race following last week's debate performance. ABC's Mary Alice Parks at the White House has more on tomorrow's interview with ABC's George Stephanopoulos. Everyone is watching for whether he can reassure Americans that he is up for the job. I think he needs to provide an honest explanation about what happened on the debate stage. We know he has told the governors that he was exhausted from international travel. There's been talk about whether he had a cold.