Voting rights advocate and prominent Georgia Democratic politician Stacey Abrams said Tuesday that mail-in ballots amid the ongoing COVID-19 pandemic could delay the election result. She warned Americans that they should not expect a presidential winner on the night of Nov. 3.

“The sheer volume of people who will be voting by mail is going to preclude the ability to count those ballots and adjudicate the outcome of the election by 11 p.m. on Election Night,” Abrams said in a virtual event hosted by Reuters.

“And so my admonition is that we have to approach Nov. 3 with patience,” she continued.

President Trump has claimed mail-in ballots would “rig” the election, although he did not provide concrete evidence to back up this claim. Last week, he even floated the idea of delaying the election due to mail-in voting.

Abrams said some states may struggle to keep up with the large number of mail-in ballots and attacked recent changes to the United States Postal Service (USPS).

"But we also can’t ignore that the president has put in place a postmaster general who is slowing down the essential delivery of mail... We know that’s going to lead to a number of legal challenges," Abrams said.

In June, Trump ally Louis DeJoy took over as the CEO of the USPS, announcing new measures to cut costs, such as eliminating overtime for hundreds of thousands of postal workers. The House Oversight Committee has invited DeJoy to appear at a September hearing to discuss these operational changes that are slowing down mail delivery across the country.

Abrams served in the Georgia House of Representatives from 2007 to 2017. She ran as the Democratic nominee for governor in the state’s 2018 gubernatorial election but lost to Georgia Republican Secretary of State Brian Kemp. Abrams has accused Kemp of using voter suppression tactics to win the election.

Abrams has been mentioned as a potential running mate for presumptive Democratic presidential nominee Joe Biden.