Actually, if you look at a county-by-county map of California in the Presidential elections, it's a lot like the map of the whole nation, and (I was surprised and enlightened to see) New York state: vastly dominated by red, with blue only along the "artsy" and/or metropolitan coast. I am proud to say that of the four coastal counties that voted Red in 2000 (out of 14 coastal counties -- California is a pretty big state), I was born in one, went to college in another, and was living and working in the third one. A fifth coastal county, Ventura, went red in one of the two Bush elections, if I remember correctly, making at one point five out of 14 (by my count) coastal counties. With I think one or two exceptions, the rest of the state was red and again, this is a BIG state in terms of sheer square miles, and 99.9 percent rural and agricultural. We feed a lot of the U.S. and a good part of the world, here.
California's turn to the left is relatively recent, and entirely due to massive population increase in tiny geographical locales.