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Electoral College under the Twelfth Amendment
Twelfth Amendment in the National ArchivesThe Twelfth Amendment changed the process whereby a President and a Vice President are elected. It did not change the composition of the Electoral College. It has applied to Presidential elections since 1804.
Under the Twelfth Amendment, each elector must cast distinct votes for President and Vice President, instead of two votes for President. Pursuant to the amendment's Habitation Clause, an elector may not vote for both candidates of a presidential ticket if both candidates inhabit the elector's state.
Still, you can pull off Cheney, who was a Texas resident in 2000 (same as Bush), and, upon being selected simply changed his residency back to Wyoming.
Yes, of course he could pull a Cheney and register in another state. That is not in question.
However, when doing so, one must take into considertion the residency requirements and the requirements one must meet in order to run for public office in that particular state, e.g. property ownership.
The Cheney case of changing registration from Texas to Wyoming was not without controversy.
Since residency requirements are varying from state to state, that would be even more controversial.
Also, I don't think Powell would pick Kemp after all. Kemp balanced well Dole, but Powell would need someone else to do the same. Jack was, at one hand, a "Bleeding heart conservative", but still was considered by some as "too moderate", due to his strong libertarian leanings. Powell would need a strong conservative, but of course credible.