text:  The incumbent expresses confidence he has a good shot at being reelected. Biden warns that any weakening of resolve ahead of next month's Democratic convention only harms the party and helps Donald Trump. NPR's Deirdre Walsh is covering Capitol Hill, where some of Biden's allies in the House have been urging the president to step aside. In the days since the president's poor performance in the debate against Republican presumptive nominee Donald Trump, five House Democrats publicly urged Biden to withdraw from the race.