What is the PC term: "White" or "Caucasian"?

I realise these terms roughly are synonyms, but I always thought Causasian was the more "politically correct" term to describe people that have the lightest skin of a population. However, I see even in academic journals when describing demographic populations, the use of the term "white" - isn't it slightly derogatory? Your thoughts? Serious and enlightened (no pun intended) answers only please.