Donald Trump spent much of the last few days insisting that the presidential election is rigged. The press, in turn, spent the same days warning darkly that Trump’s statements could gravely undermine faith in American democracy, even if—especially if—he loses in November. Many news stories quoted Republican officials dismayed by Trump’s comments.

Somehow, that did not dissuade Trump, who started the day off with another piquant, and more specific claim:

Trump’s claim, you will be surprised to find out, is unsupported. (Later in the morning, Trump retweeted a story from Alex Jones’ 9/11 Truther site, InfoWars.)

Cases of voter fraud certainly exist. But by and large, they are not the sorts of lawbreaking that the public imagines, nor are they on the scale proposed. Some, as my colleague Yoni Appelbaum wrote Sunday, involve things like poll workers futzing with numbers around the margins. Cases of invalid registration are fairly common. Not a cycle goes by without a splashy story about someone registering his or her dog to vote, only to be deluged with campaign mailers from candidates.

But these registrations seldom produce actual fraudulent votes, for the obvious reason that no poll worker is going to let Fido go into the booth. Dead voters are also often on voter rolls, but evidence of people fraudulently voting on behalf of the deceased is also rare.

In 2007, Loyola University Law Professor Justin Levitt produced a comprehensive report about fraud and concluded:

Allegations of widespread voter fraud, however, often prove greatly exaggerated. It is easy to grab headlines with a lurid claim (“Tens of thousands may be voting illegally!”); the follow-up—when any exists—is not usually deemed newsworthy. Yet on closer examination, many of the claims of voter fraud amount to a great deal of smoke without much fire. The allegations simply do not pan out.

One common rejoinder from those who believe voter fraud is a widespread problem is that such studies only show that few people are being caught for fraud. Given the cottage industry around fraud, though, one would expect widespread voter fraud to show up, which it does not. The few examples that exist tend to be sting operations like James O’Keefe’s. Others fall back on largely illusive arguments like the New Black Panther Party, a case I detailed here. Trump himself has offered no evidence to back his claim.

Trump’s claims, and those of allies like Rudy Giuliani, are the real fraud—baseless, and deleterious to democracy, because they undermine faith in the legitimacy of the political process. Just ask Ohio Secretary of State Jon Husted, a Republican who on Monday blasted Trump for “irresponsible” rhetoric.

“I can reassure Donald Trump: I am in charge of elections in Ohio, and they're not going to be rigged. I'll make sure of that,” he said. “Our institutions, like our election system is one of the bedrocks of American democracy. We should not question it or the legitimacy of it. It works very well. In places like Ohio, we make it easy to vote and hard to cheat.”

But the rhetoric is working. Four in 10 respondents in a new Politico/Morning Consult poll said they believed the election could be “stolen” from Trump, including three-quarters of Republicans.

The all-out attack on the legitimacy of American elections is being described as “unprecedented.” The New York Times quoted historian Douglas Brinkley saying that it represented the single greatest instance of delegitimizing government since the eve of the Civil War. How accurate is that, really?

Conservatives, including those not supporting Trump, have reacted with a raised eyebrow and suspicion of cynicism. What about the 2004 election, for example? In December, The New Yorker’s David Remnick reported that John Kerry suspected fraud had cost him the election:

In 2004, when Kerry lost the Presidential race to George W. Bush, who is widely considered the worst President of the modern era, he refused to challenge the results, despite his suspicion that in certain states, particularly Ohio, where the Electoral College count hinged, proxies for Bush had rigged many voting machines.

A lengthy Rolling Stone piece by Robert F. Kennedy Jr. in 2006 also argued the election had been stolen. Rumors of conspiracy were rife before the election, too, with arguments that Diebold, a major manufacturer of voting systems whose CEO was a GOP donor, would throw the election. In July 2004, 21 percent of Americans were not all that confident about election systems; by mid-October, that was up to 27 percent.

These claims are both pernicious and different from what Trump said. First, they came well after the election, rather than being rolled out ahead of time to preemptively guarantee that many voters will reject an election’s results; after all, Remnick notes that Kerry suffered his conspiracy theories in silence, conceding publicly the morning after the 2004 election, before Bush declared victory.

Trump, by contrast, has been darkly hinting that he might not concede if he loses on November 8. (His running mate Mike Pence said on CBS, “We’ll respect the outcome of this election,” putting him somewhat at odds with the other half of the ticket.) Some of Trump’s supporters warn of rebellion in the event of a Clinton victory. It’s unclear whether this view is widespread, but even the open discussion is concerning: Peaceful transfer of power is a key aspect of democracy, without which the system collapses.

There’s another way in which claims of electoral fraud have already done quite a bit to poison American democracy, however, and they have for the most part done so without widespread condemnation. Using the pretext of supposed voter fraud, a number of states across the United States have, over the last decade or so, imposed a range of laws that are ostensibly designed to combat such fraud. They include requirements that voters show ID, shorter early-voting periods, and purges of voter rolls.

Critics of these laws point out that given the scant evidence of fraud, these measures represent a solution in search of a problem. Yet they also introduce their own problems, because they disproportionately disenfranchise minority voters.

Usually, advocates of voting restrictions argue that such laws an unfortunate but necessary measure to guarantee clean elections, though others frequently trip up and say that the goal is to elect more conservative candidates. Courts have, in several cases, found these laws to represent unconstitutional voter suppression. In July, a federal appeals court struck down a North Carolina law, saying it intentionally disenfranchised blacks.

“In what comes as close to a smoking gun as we are likely to see in modern times, the State’s very justification for a challenged statute hinges explicitly on race—specifically its concern that African Americans, who had overwhelmingly voted for Democrats, had too much access to the franchise,” wrote Judge Diana Gribbon Motz.

Restrictive voting laws are only the most visible example. After losing the 2012 election, some Republicans briefly flirted with a plan to reform the electoral college, awarding electoral votes based on congressional districts—a change that would have boosted GOP chances yet produced a much less democratic result, thanks to congressional redistricting that favors Republicans.

It is heartening to see officeholders and officials on both sides of the aisle denouncing Trump for dangerous and baseless claims. But the Politico/Morning Consult poll isn’t just the product of one election cycle’s worth of allegations about voter fraud.

Many of Trump’s most widely decried claims—about immigrants, or crime rates, or government unemployment statistics—represent distorted, caricatured forms of arguments that have long circulated in political discourse, mostly on the right, for long, often with little challenge. Those arguments have produced policies that have prevented Americans from exercising their right to vote, an effect arguably closer to election rigging than anything else that has happened this cycle.