According to some legal experts over at Instapundit, California apparently has a law strictly forbidding people for being fired for political reasons.
I don't know if this is actually true, but it was discussed quite a bit last week regarding the man who was fired from Google because he wrote that memo.
That's correct, according to this website and if it were purely a Democrat or Republican issue then that might provide protection. But the Nazi and White Supremacist angle muddies the water and will likely provide the employer with all the cover they need for the termination.