So Brad Owen, the democrat could be the Lt Gov, while Rossi, of the GOP is the Gov?
Yes. The two offices are elected separately. However, Brad Owen is a "Scoop Jackson" Democrat, not your garden variety liberal.
That is correct, you can have a governor of one party and a lt. governor of the opposite party. Illinois used to be like that but I think Washington is the last state that permits a split on those two offices.