Gary Kiehne made the remarks at a Republican primary debate Saturday in Florence, southeast of Phoenix. The eastern Arizona rancher said that "99 percent of (mass shootings) have been by Democrats pulling their guns out and shooting people."
On Monday, Kiehne issued a public apology and said his comments were inaccurate. He says he shouldn't have made the remarks without any reservations.
Arizona House Speaker Andy Tobin is also running for the seat and said Kiehne should leave the race after a pattern of "bizarre and deeply offensive" remarks.
The Aug. 26 primary election will decide who faces incumbent U.S. Rep. Ann Kirkpatrick, a Democrat.
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