I believe it means that God raised him from the dead, not that he raised himself. How? That's far beyond my speculative capacities.

I believe he is called "god's son" because he is a representation of God, as it says in the book of Hebrews. A representation is never identical to that being represented, but there is some type of unity. With that said, I believe that others could possibly be representations of God if they lived a life without "sin" (there is no secular word that captures the same idea). I think he was a very capable shaman/mystic, but I do not believed he raised himself, and the bible says he didn't, so I don't think he performed any "nifty feat".