At a candidate forum on Saturday, rancher Gary Kiehne said, "If you look at all the fiascos that have occurred, 99 percent of them have been by Democrats pulling their guns out and shooting people," The Arizona Daily Star reported.
"So I don't think you have a problem with the Republicans," Kiehne added, according to the paper.
Kiehne apologized in a statement his campaign released Monday.
This past weekend, I made a comment about the political affiliation of perpetrators of gun violence in the heat of a debate. I’ve since learned that the information that I based the comment off of was inaccurate and incorrect. I’ve always believed that when you make a mistake, you should own up to it. Too many politicians today offer nothing but spin and excuses when they say something they shouldn’t have. I’m not going to do that. Simply put, I shouldn’t have made the comment, and I want to offer my apology for making it without any reservations.
Mass shootings are an especially sensitive subject in Arizona's 1st District, which borders the Tucson-based 2nd District where six people were killed in a 2011 shooting that also injured former Rep. Gabrielle Giffords (D-Ariz.) and 11 others.
Kiehne faces state Speaker Andy Tobin and state Rep. Adam Kwasman in the Republican primary, which is set for Aug. 26. The winner will take on Kirkpatrick, who is considered one of the nation's more vulnerable Democratic incumbents.