[Paloma_55]

hmm there is a correlation between people being professors and being liberal. Since Professors are in a profession that demands a high level of intelligence, is it possible that this simply means that most smart people agree with liberal philosophies?

Since intellectual pursuits often demand little in the way of physical effort, one could also infer that "Lazy people tend to be liberal".

Now this does not explain why field workers and other blue collar laborers are traditionally liberal, but then one could assume a bi-modal distribution with the lazy folks and the stupid folks combining to make up a liberal base.