(CNN) - GOP presidential candidate Herman Cain stood firm Friday on his promise to make Muslims prove loyalty to the U.S. Constitution before appointing them to his administration - a test, he has said, that would not apply to people of other faiths.
The former CEO of Godfather's Pizza denied that the proposed test is a form of discrimination when pressed Friday by CNN's John King.
"That's not discrimination. It's called trying to protect the American people," Cain said. "This nation is under attack constantly by people who want to kill all of us, so I'm going to take extra precaution."
In March, Cain made headlines when he told a Think Progress blogger that he would feel uncomfortable appointing a Muslim as a member of his cabinet or as a federal judge. And while speaking on Fox News on Wednesday, he said there was a "greater dangerous part of the Muslim faith" than other religions.
Cain told King on Friday that he would be comfortable with a Muslim serving in office only if he could gauge the person's sense of loyalty through a one-on-one conversation.
"I never said I would discriminate against Muslims or any other religion for that matter, but I am going to take extra precautions if a Muslim person who is competent wants to work in my administration," he said.
Cain has grown in popularity over recent months. The latest poll released by Quinnipiac University on June 8 puts him in third place in the 2012 GOP field, with 10%. He falls behind former Massachusetts Gov. Mitt Romney, who placed first, and former Alaska Gov. Sarah Palin, who came in second.
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