Asked Saturday evening by THE WEEKLY STANDARD for his reaction to Pate’s rebuke, Cruz defended the mailer. “Matt Schultz is a former secretary of state, he’s the chairman of our campaign, [he] put out a statement saying these mailers are routine,” Cruz said. “The Iowa Republican party has done so in the past in past elections. And I will apologize to nobody for using every tool we can to encourage Iowa voters to come out and vote.”

These type of “voter grade” mailers have been used by party organizations and political action committees, and political scientists have found they are effective in increasing turnout.

Cruz, who is appearing at a rally in Sioux City, also spoke to reporters about his challenge to Iowa frontrunner Donald Trump to debate him before the February 1 caucuses. The Texas senator criticized Trump for skipping Thursday’s Fox News debate in Des Moines.

“I believe anyone hoping to win the state of Iowa has to show the respect to the voters of this state,” Cruz said.