Secondly, home states generally vote for that candidate. Any normal Republican probably wouldn't have won Arizona, for example. That's being optimistic.
Dude, LOL. You clearly have never been here. Bachmann is the laughing stock of 7/8 of the state and about half of her district too. The Arizona example is not remotely because McCain was a statewide office holder. Bachmann hasn ever held statewide office, never will, and underran McCain about 7 points in her district. So that would give her less than 40% statewide, and she would probably underrun McCain even more in the rest of the state. Would Cynthia McKinney win Georgia as the Democratic nominee? Would Chakah Fattah win Pennsylvania? Use some basic logic.
The 2006 Senate map (with a candidate from the same district as Bachmann btw) is a good example of what a Bachmann v. Obama race would look like.