During the question and answer portion of a virtual fundraiser with former South Bend Mayor Pete Buttigieg, Biden told supporters, "I think he (Trump) is gonna try to kick back the election somehow, come up with some rationale why it can’t be held."
Trump has not suggested he would push back the election, and the date of the election is set in federal law. Congress sets the "times, places, and manner" of elections," meaning only Congress would be able to change the date of the election.
Referencing current controversy over funding for the U.S. Postal Service, Biden said, "he’s going to do all he can to make it very hard for people to vote. That’s the only way he thinks he can possibly win.”