I’ll bet he wasn’t a big lib back during the Rockford Files days. I don’t much remember Hollywood getting too political back then...I mean I know they were but nothing like the stuff you see today.
Google “James Garner politics”, and see what you get. Here’s one small sample:
“Garner is what he calls a ‘bleeding-heart liberal,’ having participated in the 1963 civil rights March on Washington and later advocating for a number of progressive causes. He voted for Dwight D. Eisenhower in 1952, he writes, but never cast a ballot for a Republican again. He voted for Adlai Stevenson in 1956, and calls him “the most intelligent presidential candidate we’ve ever had. I think Obama runs a close second.”
“He’s also critical about Charlton Heston — either as an actor or defender of civil rights. As Garner describes it, Heston appointed himself leader of the Hollywood group that went to the March on Washington, and even tamped down a suggestion by Marlon Brando that the performers chain themselves to the Lincoln Memorial. But the next year, Heston switched parties and backed Barry Goldwater.”