Mark Silk makes a fascinating point about some recent state public opinion polls. They show McCain trouncing Obama among evangelicals in Colorado but running 14%-22% points worse among evangelicals in the uppre midwest (Michigan, Minnesota and Wisconsin).
Silk, who just published a book about regional religious differences, theorizes that “Obama the Born Again Midwesterner has a greater appeal to Midwestern evangelicals than he does to evangelicals in other parts of the country–or at least than to the Dobsonian evangelicals of the Mountain West.”
I also ran these statistics by Mark Noll, one of the foremost religious historians and a professor at Notre Dame. Though he cautioned that he really didn’t know, his “stabs in the dark” theories were:

–On the religion front, Colorado Springs has become the headquarters for quite a few evangelical groups, some (but by no means all) closely identified with the New Christian Right. In MI, I’m not aware of any ideological center for evangelicals, except maybe western MI with its strong Reformed and Christian Reformed concentrations (these are traditionally Republican, but not as closely identified with the New Christian Right).
–Historically, the Upper Midwest was more strongly influenced by, first, Methodists, and then, Lutherans, two groups that, though consistently Republican, would also be pretty moderate politically throughout the 20th century. Colorado, I’m guessing, would have more of a Baptists, Church of Christ, maybe Pentecostal history.
–Depending on how the polls are done, since there are more African Americans in MI, and many of them would be religiously “evangelical,” they may be influencing the MI total toward Obama.
–On non-religious factors that may influence evangelicals similarly to all voters, inter-mountain states have been more consistently Republican in recent years than Michigan. For its part, MI has had more serious economic strains, which might open its residents generally, evangelicals included, to promises of “change.”

Any Beliefnet readers in the Midwest or West have theories about why McCain does better among Colorado evangelicals than Midwest evangelicals?