By encouraging North Carolina voters to test the integrity of the elections system by casting both mail and in-person ballots, and repeating some of the same claims in a series of tweets on Thursday, President Trump seemed to mimic a cynical slogan originating in 20th Century machine politics: Vote early and often.
Indeed, Mr. Trump’s repeated statements suggesting that the nation’s elections system is riddled with fraud fit a historical pattern — politicians in the Jim Crow South, for example, spread the myth of widespread voter fraud to encourage tighter restrictions on voting.
His comments have now created a new headache for state election officials, who are already dealing with the formidable task of holding an election during a pandemic. They insist that the type of double voting once suspected of tipping elections in big cities is virtually impossible today, citing robust systems to prevent a person from voting twice.
Douglas A. Kellner, co-chairman of the New York State Board of Elections, accused Mr. Trump of fueling concern in the minds of voters and, in doing so, adding more work to county elections boards already “stretched to the limit” by a presidential election and coronavirus.
“It’s hard to imagine how we could add any more stress to the system,” said Mr. Kellner, a Democrat.
In North Carolina, the election board released a statement on Thursday, saying that “it is illegal to vote twice in an election” and that state law “makes it a Class 1 felony.” Similar laws against intentionally voting more than once exist throughout the country, and it is also prohibited by federal law.
Elections officials in North Carolina also hinted that the president himself could have committed a crime, stating that “attempting to vote twice in an election or soliciting someone to do so also is a violation of North Carolina law.” The state’s Democratic attorney general, Josh Stein, said it was outrageous for the president to suggest that people “break the law in order to help him sow chaos in our election.”
And Jena Griswold, Colorado’s Democratic secretary of state, said, “2020 has been unprecedented in so many ways, but I never imagined that as secretary of state I would have to inform both the president and the U.S. attorney general that it is illegal to vote twice.”
That was after Attorney General William P. Barr suggested during an interview with CNN that he was not sure whether voting twice in North Carolina was illegal.
Speaking to reporters in Wilmington, N.C., on Wednesday, Mr. Trump had suggested that people who vote by mail also “then go and vote” in person as well.
“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,” Mr. Trump said, responding to a reporter’s question on election integrity. “So let them send it in, and let them go vote. And if their system is as good as they say it is, then obviously they won’t be able to vote. If it isn’t tabulated, they will be able to vote.”
On Thursday, after Facebook said it would remove video shares of Mr. Trump’s comments, suggesting they had encouraged voter fraud, Mr. Trump seemed to try to walk back those comments in a series of tweets.
“Go to your polling place to see whether or not your Mail In Vote has been tabulated (Counted.) If it has you will not be able to Vote & the Mail In System worked properly,” Mr. Trump wrote.
Election fraud is exceedingly rare in the United States, including double voting. But numerous states still have rigorous and redundant levels of checking to make sure a voter only casts a ballot once.
In North Carolina, electronic poll books are used at polling centers, and are updated regularly with information on who has voted, according to a description of its system the state released Thursday. On Election Day, voters who had already voted absentee are removed from the poll book, and ballots that are received on Election Day are not counted until after the election, when they can be checked against in-person voting to prevent any double ballots.
If a voter shows up and insists they did not cast an absentee ballot, they will be allowed to vote provisionally, which officials will also check after Election Day and decide whether it should be counted.
Officials in North Carolina warned voters not to follow Mr. Trump’s advice — even if only to check to see if their mail-in votes were recorded — because showing up in person would create confusion and increase the possibility of coronavirus exposure on Election Day. Voters can track their ballots on the state’s election website.
Many states have similar protections. In Ohio, which follows many of the same procedures as North Carolina to check against double voting, the state also has a ballot tracking system, where voters can log onto the state website and track the status of their ballot, keeping unsure voters from attempting to vote twice.
“Ohio voters are encouraged to choose one way to vote, as any additional effort to cast a ballot will not be counted and unnecessarily burdens election officials,” said Maggie Sheehan, a spokeswoman for Frank LaRose, Ohio’s Republican secretary of state.
Officials in Michigan pointed to this year’s primary elections, the most recent including a massive expansion of vote by mail, as evidence that their system was reliable.
“Our election system has been stress-tested by three successful elections already this year,” said Jocelyn Benson, the Democratic secretary of state of Michigan. “We have protections in place to ensure election officials track and verify every ballot they send and receive, and in every instance we ensure that each person gets only one vote.”
Reid Magney, a spokesman for the nonpartisan Wisconsin Elections Commission, said that each absentee ballot cast in the state is processed by poll workers on Election Day and checked against poll books to make sure the voter has not already voted in person.
In California, some counties use traditional, neighborhood-based polling places and others use larger, more centralized vote centers. At traditional polling places, voters who receive a mail ballot must surrender it if they decide to vote in person instead. At vote centers, electronic poll books allow officials to check if a voter has cast a ballot elsewhere before permitting them to vote, according to a statement issued Thursday by Sam Mahood, a spokesman for the California secretary of state, Alex Padilla, a Democrat.
In New York City, Frederic M. Umane, a Republican who sits on the city’s Board of Elections, called its system to prevent double voting “fail safe.”
Votes in New York City are immediately uploaded to a central computer, Mr. Umane said. When a voter goes to sign in, if they already voted, the system would flag it. And before any mail-in vote is counted, a check is made to see if that person also voted either in early voting or on Election Day.
Mr. Umane said the city implemented a new electronic poll book system last November and ran a series of tests beforehand to make sure it worked, adding that he was not aware of Mr. Trump’s comments this week.
“I’m a Republican,” Mr. Umane said, “but I don’t necessarily listen to everything Trump says.”