In the audio obtained by TPM, McCain warned volunteers that they will likely continue hearing from "angry" callers who are frustrated with his decision to walk away from the Republican nominee after a 2005 tape captured Trump talking about how he grabbed women by the genitals.
"He made a number of other comments and I always left it alone," McCain said, noting that Trump had gone after a Gold Star family.
McCain's remarks were made Wednesday at an event for volunteers in Phoenix, where early voting was getting underway.
McCain told volunteers that what bothered him about the Trump tape so much was not just the language itself.
"It wasn't a comment. It was a statement about what he did," McCain said. "I found that frankly something that I can't support. I have a wife, I have daughters. I'm proud to serve in the Senate with outstanding women."
McCain said without women he couldn't have been elected to the U.S. Senate.
"All I can say is there are a lot of angry people out there, and you're hearing from 'em on the phones and all I can do is tell ya that I have to examine my conscience," McCain said.
The audio is illuminating as it shows how the senator came to his decision to abandon Trump after pledging in his primary that he was backing the nominee.
"I do what I believe is right. I am a loyal Republican, but I also have an obligation to the people of Arizona whether they're Republican or Democratic or whatever," McCain said. “So I know that you are going to get a lot of feedback on the phone about my decision, and all I can tell you my dear friends is there are times in my political life when I've done things for political reasons, I’ve always regretted it. When I’ve done things because they were the right thing to do, I’ve never regretted it.
The room applauded.
"I would be letting you down, I would be letting you down," McCain told the volunteers.
Listen to the full audio: