It's funny, I've met one prof who was openly conservative and he happened to be a math professor. I had him for stats and not only loved him as a teacher but for ones found a math that I absolutely loved.
Actually, it's fairly easy to be an open conservative in disciplines where a lot of the faculty are emigres from former Communist countries. The leftists pipe down and you have supportive colleagues--they recognize the stench of the left instinctively.