text:  Live from NPR News, I'm Lakshmi Singh. Democratic members of Congress are meeting behind closed doors the day after President Biden sent them a letter to declare he has no intention of ending his re-election campaign. Biden's debate performance against his predecessor last month raised red flags about his acuity and prompted calls among some Democratic lawmakers to withdraw from the race. While the top Democrat in the House, Representative Jerry Nadler of New York, is still backing Biden...