Former Vice President Joe Biden participates in a discussion on bridging political and partisan divides with Ohio Gov. John Kasich at the University of Delaware in Newark, Del., last month.
Khizr Khan, father of fallen US Army Capt. Humayun S. M. Khan, speaks during the final day of the 2016 Democratic National Convention, as his wife listens. Since, then Khan has openly feuded with Donald Trump in the media
J. Scott Applewhite/AP