Biden says he won’t drop out as some Democrats question his ability

 President Joe Biden refused to abandon his reelection campaign on Monday as he sought to stave off a possible revolt by fellow Democrats who worry the party could lose the White House and Congress in the Nov. 5 U.S. election.

Biden, 81, said any candidates who doubt his ability should challenge him at the Democratic National Convention in August – an effort that stands no chance of success unless he lets the delegates he won in primaries this year consider other candidates.

“The...