If you're familiar with the groups in question, it seems sort of odd that urban Episcopalians or Methodists would really have common interests with suburban non-denominationals, but these groups together were voting solidly Republican long before rural Baptists did. I think you would really see a distinction if there were an abortion referendum. Perhaps the most representative politician of this social class is Kay Bailey Hutchison, who lives in a rich part of Dallas and who of course identified herself as pro-choice.
Because one of the most distinctive political characteristics of the South is opposition to abortion and because these people tend to have religious affiliations that are not recognizably Southern, it's tempting to characterize them as northern, but in fact people like this do not exist outside the South. The Gold Coast of Chicago does not vote Republican.
The fact that there aren't equivalents to this outside the South is interesting to me and I think is revealing as to the specifically southern character of these sorts of places. Chicago is one thing, but even cities of a comparable vintage and land use outside the south don't vote this way.
There were equivalents to this outside the South in the 20th century. Upper-crust Northern suburbs turned in overwhelmingly Republican majorities unfailingly from 1920-1960. Upper crust Northern areas with the density/ethnic composition of wealthy Southern areas were still voting Republican in 2014.
