CNN

Watch CNN's John King interview McCain Wednesday.

LOS ANGELES, California (CNN) - Sen. John McCain called on his embattled Republican colleague Sen. Larry Craig to resign Wednesday, two days after it was first reported that the Idaho Republican was arrested in an airport bathroom and pleaded guilty to disorderly conduct.

"I believe that he pled guilty and he had the option to plead innocent," McCain told CNN's John King. "So I think he should resign."

"My opinion is that when you plead guilty to a crime you shouldn't serve," the Arizona Republican added. "That's not a moral stand, 'holier than thou,' just a factual situation."

"In this case it's clear it was disgraceful," McCain continued.

Yesterday, Craig spoke before cameras in Boise, Idaho, where he insisted that he did nothing wrong and said several times that he was not gay.

McCain also spoke out about his struggling campaign for president. The Arizona senator said his campaign is doing fine and added he is the most experienced and most prepared of all the candidates for the White House.

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