Donald Trump unleashed a Twitter rant today accusing Ted Cruz of stealing the Iowa Caucus and calling for the results to be nullified.

I knew something like this was coming and quite frankly I’m surprised it took Trump so long to play the voter fraud card. It’s a logical extension of his demonization of Hispanics, Muslims, refugees and all the other people he believes are preventing America from being great again.

It’s become an article of faith among Republicans that Democrats must cheat to win elections. The only difference here is that Trump is accusing another Republican of doing so.

The GOP’s fraud crusade goes back to the George W. Bush administration. The 2000 election in Florida, which was marred by a disastrous voter purge of alleged ex-felons, empowered a new right-wing voter fraud movement, which hyped the threat of fraud in order to restrict access to the ballot for partisan gains. The Justice Department was taken over by ultra-conservatives like Attorney General John Ashcroft who made combating fraud a top priority. US Attorneys in states like New Mexico and Washington were fired for not undertaking new prosecutions, and new voting restrictions, like Georgia’s voter ID law, were approved by the DOJ’s Civil Rights Division over objections from career lawyers. Rick Hasen dubbed these people the “fraudulent fraud squad.” (I write extensively about this in my book Give Us the Ballot.)

Though little fraud was ever found, the fraud craze grew much louder when Barack Obama ran for president. John McCain alleged in 2008 that ACORN “is now on the verge of maybe perpetrating one of the greatest frauds in voter history.” After the election, one poll found that 52 percent of Republicans believed that ACORN had stolen the election for Obama.

There was no proof of this, but the incessant drumbeat of fraud accusations became a useful pretext for Republicans to push new laws making it harder for Democratic-leaning constituencies to vote, such as voter-ID laws and restrictions on voter registration and early voting. The Republican fixation with voter fraud became a “new Southern strategy,” the Rutgers University political science professor Lori Minnite wrote in her book The Myth of Voter Fraud. “The reddest base of the Republican Party has been energized by the tarring of Democrats as cheaters and the association of Democrats with a radicalized crime-prone underclass.”

Today, all of the leading Republican candidates for president support efforts to make it harder to vote and have exaggerated the threat of voter fraud. During a campaign stop in South Carolina in November, Cruz nodded when a questioner asserted that Obama was elected in 2008 because of fraud. “We have to win by a big enough margin so they can’t steal the election,” Cruz replied.

Trump may be the loudest voice in the room, but, unfortunately, on this issue he’s far from alone.