“Mark my words, I think he is gonna try to kick back the election somehow, come up with some rationale why it can’t be held,” said Mr Biden during an online campaign event, according to a pool report. “That’s the only way he thinks he can possibly win.”
The Democrat has maintained that the election should take place in November despite concerns around in-person voting and the current postponement of primaries in numerous states.
“I’d much prefer to have on — you know, in-person voting, but it depends. It depends on the state of play,” Mr Biden told NBC in an interview on April 7. “But we cannot, we cannot delay or postpone a constitutionally required November election.”
Democrat concerns come despite Mr Trump not having the unilateral power to postpone the November election, which would need the approval of both houses of the US Congress. One of which, the US House of Representatives, is held by Democrats.
On Thursday, Mr Biden said that states needed more financial support from Congress to prepare safe methods of voting in November.
He referenced how Wisconsin Republicans had blocked Democrat attempts to delay the state’s primary on April 7 and extend the deadline for returning mail ballots.
“Republicans were trying to force in-person voting no matter the health cost. We have to figure out how we are going to conduct a full and fair and safe election in November, and no one should have to risk their lives to cast a ballot,” added Mr Biden.
Senate Republicans and the Trump administration have pushed-back on Democrat attempts to attach funding for the expansion of general election mail-in voting to the latest coronavirus emergency package.
“The idea you had all the governors and so many mayors -- Republican and Democrat -- asking the President and asking (Senate Majority Leader) Mitch McConnell, ‘We need local funding for our local support, for the things we have to do,’ “ continued Mr Biden on Thursday.
“I think it’s absolutely mindless, mindless, that they are unwilling to do it. I don’t get it. I don’t get it.”
Mr Trump has been condemned over past comments on false claims of “corrupt” mail voting, whilst critics point out that the president is able to vote by mail.