A new post-Caucus Survey USA poll of Iowa registered voters shows, among other things, Obama trouncing all Republicans (especially Rudy). The highlights:

Obama defeats McCain by 17 points.

Obama defeats Huckabee by 23 points.

Obama defeats Romney by 26 points.

Obama defeats Giuliani by 40 points.

McCain defeats Clinton by 4 points.

Huckabee and Clinton tie.

Clinton defeats Romney by 8 points.

Clinton defeats Giuliani by 16 points.