text:  Live from NPR News, I'm Dale Willman. After a week of doubts from Democrats provoked by a poor debate performance, President Biden is pushing ahead with his 2024 campaign. And in his first televised interview since the debate last week, Biden defended his ability to serve another four years. NPR's Elena Moore reports. Speaking with George Stephanopoulos of ABC News, President Biden acknowledged he was worn down ahead of the debate and it contributed to his performance. It was a bad episode. I