 In the United States, more senior Democrats have said they want Joe Biden to step aside as the party's presidential nominee. The latest defections include several House committee leaders who expressed their views in a private call organized by House Minority Leader Hakeem Jeffries. But the U.S. president has vowed to stay in the race and in an exclusive interview with ABC's George Stephanopoulos, Biden insisted that he is sharp enough to do the job for another term. I have a cognitive test every single day.