Here's what President Trump was referring to when he said fraud has been 'established' with mail-in voting

President Donald Trump said during Tuesday night's first presidential debate that fraud has already been "established" as a risk with mail-in voting, citing a recent race between two Democrats.

What are the details?

As the debate began to wrap up, Trump pushed back on Democratic presidential nominee Joe Biden's claim that "no one has established at all that there is fraud related to mail-in ballots. That somehow it's a fraudulent process."

"It's already been established," the president replied. "Take a look at Carolyn Maloney's race," Trump suggested to moderator Chris Wallace. "Look at Carolyn Maloney. They have no idea what happened."

President Trump was not able to elaborate as Wallace returned the floor to Biden, who said that the president "has no idea what he's talking about."

What President Trump was referring to was a June primary race between incumbent Rep. Carolyn Maloney (D-N.Y.) and her challenger, fellow Democrat Suraj Patel.

Patel did not concede for more than two months, because, according to India West, the "results were delayed and contested due to problems counting absentee ballots." Neither of the candidates alleged fraudulent or duplicate voting, but they did allege that some ballots were improperly not counted.

Fox News reported last month that the Maloney-Patel race and another New York race "mired by thousands of missing and uncounted mail-in ballots" have "become Exhibit A in President Trump's campaign against universal mail-in balloting, which he and several experts say poses a major fraud risk."

The outlet explained:

Maloney held onto a mere 658-vote lead over Patel after in-person voting concluded, with 65,000 mail-in votes uncounted. The final, certified margin of victory was 3,700 votes. A total of 13,000 mail-in votes were tossed out for various reasons, including missing signatures or incorrect postmarks.

President Trump called for a do-over in the Maloney race, referring to it as a "total disaster."

Fox News also reported that "fraud has not been alleged in the race," but acknowledged that "a Fox News analysis found a slew of issues in other states in recent days, including intentional ballot fraud."

In reaction to Trump bringing up the Maloney race as an example, Patel tweeted Tuesday night, "Let's be clear, the issue in my race was disenfranchisement, not voter fraud. More than 1 in 5 ballots were discarded, many multiples of the final margin. We called our election a canary in the coal mine for November, we were right. Trump lied about what happened here."

Maloney herself did not address the fraud allegations when she tweeted, "Donald: I won my election. You're going to lose yours."