When President Donald Trump was asked during Tuesday's debate whether he would urge his supporters to be patient during the extended voting process in this year's election, the Republican incumbent would not commit. "If I see tens of thousands of ballots being manipulated, I can't go along with that," Trump said, making unsupported -- but now familiar -- claims about voting by mail. He also urged his supporters to go to the polls and "and watch very carefully."

Throughout the COVID-19 pandemic that has led to a surge in interest in mail-in ballots, Trump has repeatedly warned against potential voter fraud. However, members of his own administration say there’s “no real evidence” of that threat, according to PBS NewsHour reporting.

Voting fraud does occur, infrequently, but analyses indicate few instances of fraud are due to vote-by-mail. One Stanford University study of three of the five states with all-mail elections determined that they do not heavily favor one party.

During the debate, Biden rejected Trump's claims about the process, saying that voting by mail is "honest" and that "no one has established at all that there is fraud related to mail-in ballots."

Biden and Trump faced each other in Cleveland, Ohio, on Sept. 29 for the first of three debates before voting concludes in November. Despite meeting in person, the event included an audience of about 80 people, hosted by the Cleveland Clinic and Case Western Reserve University.

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