DES MOINES, Iowa — In the latest and most historically accurate poll from Iowa, Republican presidential candidate Ted Cruz fell short of his opponent, Donald Trump, by five points. The Des Moines Register poll was released just one day before voters in the state caucus for their candidate of choice, and it shows that Cruz's deficit is substantial.

Per reports, it appears that the Cruz campaign is doing everything that it can to increase turnout, including sending out "voting violation" mailers to pressure residents to get out and caucus for the candidate.

Not only does the mailer attempt to manipulate voters by using "social pressure" and a seemingly official letter to encourage Iowa residents to caucus for Cruz — threatening to release individual voter data to the public — that data is likely made up, The New Yorker reported.

So basically, residents in Iowa are receiving "voting violation" letters that look official (but are really from the Cruz campaign) and they're causing controversy because the voting history information the campaign included in the mailers is possibly fabricated.

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"VOTING VIOLATION," the text at the top of the letter reads.

"You are receiving this election notice because of low expected voter turnout in your area. Your individual voting history as well as your neighbors’ are public record. Their scores are published below, and many of them will see your score as well. CAUCUS ON MONDAY TO IMPROVE YOUR SCORE and please encourage your neighbors to caucus as well. A follow-up notice may be issued following Monday’s caucuses."

It's a campaign strategy based in political science. A 2006 study conducted by researchers at Yale and the University of Northern Iowa found that peer pressure — such as mailing letters that grade voters based on their past voting behavior — could have a positive impact on voter turnout. They mailed more than 180,000 letters that informed residents in Michigan that they were part of a study and that the researchers would "publicize who does and does not vote."

"The letter worked," the Washington Post reported. "Political consultants, like Democrat Hal Malchow, found that similar letters in real elections could boost turnout by up to 2.5 percent."

/Kyle Jaeger