Except that that was a primary election, not the general election. The Senate rules said that the winning candidate of the general election had to be a resident of the state, and the dead aren't residents. Carnahan should have been disqualified, unless the courts wanted to extrapolate from one ruling to another. I can see creating a vacancy with intent for the primary, but not the real thing. Voters would be giving up their constitutional right to elect Senators if they intentionally created a vacancy to be filled by the governor.
-PJ