Ari Berman, a senior contributing writer for the Nation, is the author of “Give Us the Ballot: The Modern Struggle for Voting Rights in America.”

Nothing to see here: a New Hampshire polling station this February. (AP Photo/David Goldman)

In a span of two weeks, federal courts have struck down Republican-backed voting restrictions in six states, including laws that required strict forms of government-issued ID in order to cast a ballot, cut back on early-voting days and made it harder to register. The rulings found that the laws — in Texas, North Carolina, Michigan, North Dakota, Kansas and Wisconsin — violated the Voting Rights Act by discriminating against people of color, sometimes “with almost surgical precision.”

Rather than seeing these rulings as a victory for democracy, Donald Trump says they will lead to a record number of fraudulent votes for Hillary Clinton in November. “The voter-ID situation has turned out to be a very unfair development,” Trump told The Washington Post. “We may have people vote 10 times. . . . Why not? If you don’t have voter ID, you can just keep voting and voting and voting.”

Republican presidential nominee Donald Trump told supporters in Columbus, Ohio, Aug. 1 that he worries the Nov. 8 election "is going to be rigged." (The Washington Post)

Just how easy would it be to rig a Presidential election, as Trump suggests Democrats are preparing to do? How many people would it require, what tactics would they have to use, and how many votes would they need to flip a major contest or state?

The most common schemes to steal elections involve old-fashioned vote buying, using absentee ballots that are cast without the supervision of poll workers. During a 1996 primary election in rural Dodge County, Ga., rival candidates in the sheriff and county commissioner races went so far as to set up vote-buying tables at opposite ends of the county courthouse, offering voters $20 to $60 per ballot. County officials likened it to “an auction” or “a flea market.” One race was decided by nine votes, the other by 31.

The not-so-subtle scheme, however, soon attracted federal scrutiny. Absentee ballots accounted for 15 percent of the total votes, in a state where they rarely exceeded 10 percent. And many residents of the county were in on the fraud or knew about it. Forty voters testified at a federal trial that they were paid by one side or the other, and a grand jury indicted 21 locals, a record number for illegal vote buying. The results were overturned, and new elections were held under federal supervision.

There’s the rub: Large-scale voter fraud is usually easy to detect and can rarely sway anything but close local races. “The more people it takes to pull off a form of fraud, the more likely you are to get caught,” says Wendy Weiser, director of the democracy program at the Brennan Center for Justice. “To the extent that there are absentee-ballot fraud scandals, they are in local elections. You could never do it on the scale to effect a congressional, statewide or national race.”

Another strategy for stealing an election is to find someone on the inside. In Cudahy, Calif., in Los Angeles County, city officials in 2007 and 2009 systematically opened secret ballots, then resealed and counted them if they were cast for incumbents, or discarded them if they were not.

This sort of scheme can be successful in one or two local elections, but it’s difficult to keep secret — the city manager and mayor confessed to the election rigging after pleading guilty to bribery and extortion. Moreover, it wouldn’t be possible in a state or federal election, in which the counting of ballots is closely monitored.

Someone could also try to manipulate an election result by tampering with electronic voting machines, especially in the 14 states where there is no verifiable paper trail. The machines could be modified by election officials or hacked by outsiders, a particular concern after recent hack of the Democratic National Committee. “We are actively thinking about election cybersecurity,” Homeland Security Secretary Jeh Johnson said this past week, announcing that the Obama administration is planning new steps to protect the country’s voting systems.

But with the rare exception, such as in a small Kentucky county, elections have not been decided by corrupting the results of electronic voting machines. Nor do Republicans like Trump focus on this as a major threat, perhaps because it’s been a much greater concern on the left than on the right.

Election experts agree that voter impersonation fraud — which voter-ID laws are meant to address — is exceedingly rare and the most inefficient way to steal an election. Every state requires some proof of identity at the polls, whether it’s providing your name and address at the correct precinct, signing a matching signature, or showing a form of ID (a voter registration card, utility bill or driver’s license). “Donald Trump said people are voting 10 times — I’d like to see him try to do that,” says Lorraine Minnite, a political scientist at Rutgers University at Camden and the author of “The Myth of Voter Fraud.”

If Trump wanted to vote 10 times in New York — a state that requires voters to sign their names at the polls rather than show a photo ID — he’d have to vote in 10 different places, know the names and addresses of nine other registered voters in nine other precincts, be able to forge their exact signatures, and know that they hadn’t voted yet. Each fraudulent vote would carry a penalty of five years in jail and a $10,000 fine, plus additional state penalties.

The risk of getting caught for voter impersonation far outweighs the reward of a few extra votes. That’s why there have been only 31 credible incidents of impersonation out of 1 billion votes cast in the United States since 2000 . In comparison, there are about 30 deaths by lightning in the country each year. “I could not find a single example from the 1980s onward where voter impersonation could have swung one election or that there was any kind of conspiracy to do so,” says Rick Hasen, a law professor at the University of California at Irvine and the author of “The Voting Wars.”

Indeed, in the past Trump has had difficulty voting once, let alone 10 times. In 2004, he had to visit three polling places because his son Donald Trump Jr. had moved to a new address, which inadvertently changed Trump’s polling location, too. He angrily cast a provisional ballot after his name wasn’t on the rolls at any of the sites.

Voter-ID laws in states such as North Carolina actually make voter fraud morelikely by requiring strict ID for in-person voting, where fraud is rare, but exempting the ID requirement from absentee ballots, where fraud is more common, thus encouraging some voters to cast ballots using a less-secure method. An exhaustive study of 2,068 alleged election-fraud cases since 2000 by News21, a project of Arizona State University, found 10 cases of voter impersonation vs. 491 cases of absentee-ballot fraud (which is still quite unusual and rarely determines the outcome of an election).

By questioning the integrity of the ballot, Trump is merely amplifying a strategy the GOP has pursued for two decades, one less about stopping fraud than about making it harder for Democratic-leaning constituencies to vote. John McCain said in 2008 that ACORN, the liberal political organizing group, was “on the verge of maybe perpetrating one of the greatest frauds in voter history.” In 2012, after TV networks called the election for President Obama, Trump went on a Twitter rant about the electoral college. “This election is a total sham and a travesty,” he tweeted. “We are not a democracy!” Minnite has called the GOP’s fixation with voter fraud “a new Southern strategy” that has energized the Republican base by “tarring . . . Democrats as cheaters.”

The real threat of election-rigging lies not in the small number of voting irregularities, which Trump and many Republicans have blown wildly out of proportion, but in the much larger number of people disenfranchised by new voting restrictions. “A preoccupation with mostly phantom election fraud leads to real incidents of disenfranchisement, which undermine rather than enhance confidence in elections,” U.S. District Judge James Peterson wrote in a decision striking down Wisconsin’s voting restrictions on July 29.

In North Carolina, for example, the watchdog group Democracy North Carolina documented more than 2,300 cases of voters whose ballots were rejected in 2014 because of the state’s elimination of same-day registration and out-of-precinct voting. That was 1,150 times greater than the two cases of voter impersonation committed in North Carolina from 2002 to 2012, out of 35 million votes cast.

In the end, it’s much easier to lose your rightful vote than to gain an extra one.