WASHINGTON ― In the weeks leading up to Election Day, the voter fraud claims were flying.

A prominent Republican warned about voter fraud in “urban areas” and the “inner city.” A top Republican lawyer said voter fraud was an “epidemic.” Fox News set up a hotline to collect voter fraud allegations from their viewers. A conservative media figure suggested citizens acting as “voter fraud police” were needed to keep an eye out for malfeasance, and volunteers signed up by the hundreds to get involved in poll watching. Soon, aggressive poll monitors were accused of “hovering over” voters in communities of color as early voting got underway.

Then a funny thing happened. After the 2010 midterm election ― when Democrats took what President Barack Obama called a “shellacking,” and Republicans regained control of the House and won back seats in the Senate ― those concerns about widespread voter fraud sort of faded away.

Six years later, Republican presidential nominee Donald Trump ― who built his political career by questioning the legitimacy of the first black president ― has a new favorite conspiracy theory. Lagging badly in the polls (The Huffington Post’s forecast currently gives him a 6.5 percent chance of beating Democratic nominee Hillary Clinton), Trump has been suggesting over and over that the country’s largely decentralized and state-run election process is somehow rigged against him. There’s “large-scale voter fraud” happening all over the place, Trump claims. No, he doesn’t have any evidence, but it’s happening. Trust him.

Of course there is large scale voter fraud happening on and before election day. Why do Republican leaders deny what is going on? So naive! — Donald J. Trump (@realDonaldTrump) October 17, 2016

This shouldn’t really surprise anyone. Trump has been talking about voter fraud for months ― typically warning rural, mostly white crowds that electoral malfeasance in urban districts, where lots of people of color live, will tilt the election to Clinton. Now, we have evidence that Trump’s supporters are taking those warnings seriously.

A recent poll found that 72 percent of Trump supporters think “a lot” or “some” voter fraud happens in their state. And The Boston Globe’s Tracy Jan and Matt Viser recently interviewed a number of Trump enthusiasts convinced that Clinton’s allies will try to steal the election. Several said they planned to heed Trump’s call to serve as election monitors. One man, a 61-year-old carpenter from Ohio, explained that he’d be paying particular attention to “Mexicans. Syrians. People who can’t speak American.”

“I’m going to go right up behind them,” the carpenter said. “I’ll do everything legally. I want to see if they are accountable. I’m not going to do anything illegal. I’m going to make them a little bit nervous.”

Even in a presidential campaign as surreal as this one, Trump’s claims about voter fraud stand out. It hasn’t only been Obama commenting on Trump’s “whining.” Some Republicans have sought to downplay or dismiss Trump’s claims that the entire electoral system ― which in many key swing states is controlled by Republicans ― is a giant conspiracy that will be to blame when he loses.

Jonathan Ernst / Reuters

House Speaker Paul Ryan (R-Wis.) last week released a statement affirming that he “is fully confident the states will carry out this election with integrity.” Republican Ohio Secretary of State Jon Husted, who has said he is voting for Trump, has called Trump’s talk about a “rigged” election “irresponsible.” (Husted, for the record, has been involved in the rollback of early voting in Ohio, which has a disproportionate effect on black voters.) Sens. Marco Rubio (R-Fla.) and Patrick Toomey (R-Pa.) have both rejected Trump’s claims of a rigged election.

But even though some key Republicans are seeking to distance themselves from Trump’s rhetoric, it’s worth putting their comments in context.

For decades, Republicans and their conservative allies have been making dire claims about voter fraud, whipping their base into a near-frenzy over a problem that, according to every reliable authority and study, is not a major factor in elections. (PolitiFact, which gave Trump’s statement on voter fraud a “pants on fire” rating, cites a number of studies that show just how rare in-person voter fraud is.) They’ve been doing so, in many cases, to justify efforts that look suspiciously like a campaign to suppress votes in Democratic-leaning communities of color.

To put it another way, Trump didn’t build the voter fraud myth. Republicans helped make that happen.

Here’s how deep the GOP’s connection to the voter fraud myth goes: The Republican National Committee is subject to decades-old court-imposed restrictions on its ability to challenge voters’ eligibility at the polls. Those restrictions on the RNC’s so-called “ballot security” efforts date back to 1982 and aren’t set to expire until December 2017. (Republicans in key positions at the RNC aren’t immune to the voter fraud myth: Politico spoke with more than a dozen RNC members who agree with Trump that the process is “rigged.”)

Election law expert Rick Hasen, whose 2013 book The Voting Wars has a chapter on the “Fraudulent Fraud Squad,” said it’s important to look at the history of these claims of widespread voter fraud, which have popped up before every election in recent history.

“It has primed the Republican base, and especially Trump supporters, to believe that Democrats are routinely stealing elections,” Hasen told The Huffington Post. “Dead voters, people of color, labor unions, Democratic machine, George Soros, New Black Panthers ― roll it all into one and that’s how they see elections taking place in places like Philadelphia. The polling shows that it’s having an effect on these voters, and it makes me concerned that they will not accept the results of this election, even if it is not close.”

Hasen says he expects issues to come up in cities in battleground states that have high percentages of people of color.

“The only thing that gives me solace,” he said, “is that the Trump campaign seems to be so behind the game on organization that it’s not going to have any organized efforts that could potentially intimidate voters.”

Lorraine Minnite, the author of the 2010 book The Myth of Voter Fraud, said Trump’s comments suggest he knows he’s not going to win.

“I’m guessing that part of it is he’s preparing to lose the election, and he wants to be able to say that he didn’t actually lose the election,” she said. “I just don’t think he cares about the effects of what he says.”

Minnite, whose research found that in-person voter fraud is extraordinarily rare and largely a politically constructed myth, said it’s discouraging how many Americans are convinced that in-person voter fraud is actually a widespread problem.

“After all these years of saying it’s not true, I’ve practically given up on it,” Minnite said. “I’d like to know what would work, but I fear it won’t work, because it’s not about facts. It’s about deeper emotional issues for people.”

Additional reporting by Jonathan Cohn.

Editor’s note: Donald Trump regularly incites political violence and is a serial liar, rampant xenophobe, racist, misogynist and birther who has repeatedly pledged to ban all Muslims — 1.6 billion members of an entire religion — from entering the U.S.