Republican turned independent thinks Democrats can save the GOP

"One of the institutions that the Democratic Party may wind up saving in its defeat of Trumpism is the Republican Party itself," Schmidt told David Axelrod on the "Axe Files," a podcast from The University of Chicago Institute of Politics and CNN.

Schmidt said he finds himself "optimistic about our future," looks forward to the 2020 election and expects to be part of a campaign in some capacity, "more likely as a volunteer than a principal architect, but being involved in an effort to renew the promise, the idea and the ideals of the country."

The "outspoken Never Trumper," as Axelrod put it, has made a major shift in his political ideologies since running the late Sen. John McCain's campaign as the Republican presidential nominee in 2008.

Here are key moments from Schmidt's involvement in politics:

1. The McCain team felt they needed to 'do something disruptive'

Schmidt knew the McCain campaign had to make a strategically bold choice in order to "have any chance in the election against Barack Obama," who he viewed as "the heavyweight champ" heading into 2008 presidential debates.

Leaning into McCain's time in the military was one way, according to Schmidt, that the campaign could have a serious chance.

"My idea was that John McCain was going to go out and say, 'I put the uniform of my country on when I was 17 years old.' "

This "disruptive" strategy included, in Schmidt's opinion, making a bold promise.

"What he would have said was, 'I promise to serve for only four years. We will fix these problems. ... Barack Obama is a good man, and I think, I know, he'll be president of the United States someday. He surely will, but he's not ready quite yet.' "

2. Palin wasn't 'fully vetted,' according to Schmidt

"To this day, the people in charge of vetting her insist the vet was full, it was complete and it was well done. ... Three days after we pick her, I found out she doesn't know where Iraq and Afghanistan are on a map. She doesn't know that Iraq didn't attack us on 9/11."

Schmidt said he wasn't a part of the vetting process himself, which he acknowledges today as a "mistake" and "regret."

McCain had invited Schmidt to join one of his last conversations with Palin before confirming her as his running mate, but Schmidt declined, telling McCain it was "completely inappropriate."

"They went off for an hour. He came out. No person alive except for Sarah Palin knows what was said, what was talked about in that meeting. I wish I did."

3. Schmidt became critical of Palin

Looking back, Schmidt said that to this day he is "sickened by (Palin) now at a psychological level and a character level, the constant lying, all of it."

"Palin is the first professional victim in an era where victimization becomes the lifeblood of the Republican Party, where it becomes virtuous," he said.

Schmidt saw Palin as "unfit" to be vice president, an example being the way she responded to the crowds at rallies.

"She wasn't purposefully divisive, because she was too ignorant to be so. She was just transactionally exploitive. She was drawn to the fame. ... She wanted to be a celebrity. The campaign made her famous."

4. Schmidt doesn't regret his falling out with McCain

Schmidt, along with several of his colleagues, was not invited to McCain's funeral, which left him "humiliated."

"More than any other person I have met, he was my inspiration to stand up, damn the consequences, and fight for what you believe in, and do what you think is the right thing to do. What I thought the right thing to do was to talk honestly and openly about (Palin's) manifest unfitness."

He says his outspokenness about Palin is what led to the "rupture" of his relationship with McCain. But he doesn't regret it.

"As painful as it may have been, I would do it again, and again, and again, and again. ... And the cost of a relationship that was amongst the deepest and most intimate that I'll ever have in my life was a profoundly painful thing. But worth the cost."