By JORDYN PHELPS, ABC News

(WASHINGTON) — President Donald Trump has long sought to undermine public confidence in the upcoming election with baseless warnings that mail-in-voting could lead to widespread voter fraud.

And on Wednesday, in the battleground state of North Carolina, he suggested to supporters that they should attempt to vote twice — first by mail and then in person.

“They will vote and then they are going to have to check their vote by going to the poll and voting that way because if it tabulates then they won’t be able to do that. So, let them send it in, and let them go vote,” Trump said Wednesday in an interview with North Carolina news station WECT-TV.

He continued: “And if the system is as good as they say it is, then they obviously won’t be able to vote. If it isn’t tabulated, they will be able to vote. So that’s the way it is, and that’s what they should do.”

It is illegal to vote twice. And while election laws vary by state, it would amount to a Class I felony offense in North Carolina.

Attorney General Bill Barr, asked to explain the president’s comments in an interview on CNN Wednesday, said he wasn’t sure exactly what the president meant but didn’t dismiss the idea outright.

“I don’t know exactly what he was saying, but it seems to me what he’s saying is, he’s trying to make the point that the ability to monitor this system is not good,” Barr said. “And if it was so good, if you tried to vote a second time you would be caught if you voted in person.”

The president’s comments come as poll after poll show him trailing his Democratic opponent Joe Biden and under scrutiny for his handling of the coronavirus pandemic, which has resulted in more than six million infections in the U.S. and nearly 185,000 deaths.

The president’s comments were the latest evolution in a months-long rhetorical campaign by the president to undercut public trust in the upcoming election. He has relentlessly repeated unsubstantiated claims that the expected increase in mail-in-voting due to the coronavirus could result in 2020 being the “most rigged election in history.”

Anticipating his predictions of fraud, Trump has declined to commit to accepting the results of the election if things don’t go his way.

“The only way we’re going to lose this election is if this election is rigged,” Trump said last month in Wisconsin.

Experts and election officials across the country have pushed back against the president’s assertion that mail-in voting could discredit an election.

“Voting by mail is not some kind of new, untested innovation,” Dale Ho, director of the ACLU’s Voting Rights Project, told ABC News. “We’ve been using it in this country since the Civil War. And I think over 80 percent of Americans live in states that have committed to letting every eligible voter cast a ballot by mail in November. So it’s not something kind of new or crazy. It’s been something that people in this country have been doing for over a century.”

ABC News reached out to elections authorities in all 50 states for their assessment of Trump’s claims. Of the nearly 30 secretaries of state and elections board offices who provided on-the-record responses in July none expressed doubts in their state’s ability to protect the integrity of their elections this November.

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