On the stump, in interviews, at just about every chance, President Trump warns that the voting already taking place in America is rife with fraud.
"Every day they're talking about ballots that are corrupt, that are fraudulent," he told NBC's Savannah Guthrie in a town hall Thursday night.
There's just one problem.
Election officials from both parties say there is virtually no evidence of such fraud anywhere in the United States.
"The vote-by-mail system is every bit as secure as voting in person," said Matt Dietrich, spokesman for the Illinois State Board of Elections. "The ultimate standard that is used to verify those ballots is the voter's signature."
Across Illinois, some 2,238,606 voters had requested ballots as of Friday, and 642,776 had been returned, according to State Election Board records.
NBC 5 asked the Chicago Election Board to walk us through the process of what happens after you drop your ballot in the mailbox. It's a process that's unfolding every day in the board's offices near the Daley Center downtown.
Arriving ballots, still sealed in their envelopes, are first run through a giant machine called an "Agilis", which scans the signatures which voters are required to sign on the outside. Those are electronically matched with the voter's permanent record in the election rolls.
Upstairs, teams of election judges sit before giant screens, examining each scanned signature against its permanent counterpart. Most pass muster quickly. A few are found obviously mismatched, and those are kicked out of the running. The voters are contacted for verification, and may be asked to come in and re-vote.
After that, the envelopes are run through the machine again, this time to sort them by ward. Then, they are opened by still another machine, and another team of judges removes the ballots, initials them, and sends them to be scanned into the system.
That data is stored, and will appear as the first votes counted after 7 p.m. on election night.
It's a multi-step process, but the key is the signature. And that addresses one of the biggest fears raised by opponents — that somehow thousands of ballots will be harvested by evil-doers, filled out in their basements, then sent back en masse.
To do so, notes Dietrich, would require the perpetrator to successfully forge all of those signatures so they match the names on the registration forms to such an extent that they fool a trio of judges.
"It's secure, we secure it the same way we secure ballots at in-person polling places," he told NBC 5. "It's a very safe system."