Why is the South so conservative?

[Badger]

Religious fundamentalism.

Unlike like most areas in the Northeast and Midwest, Evangelical church membership is higher than "Mainline" church attendance in the Southeast.   

I wouldn't say that's the main cause although it is one of many. I mean states like Idaho,  Alaska, and Montana are pretty conservative overall, but they have some of the lowest church attendance/importance of religion in daily life rates in the country.

Likewise states in the Northeast like MA and RI have large numbers of Catholic voters, but are still solidly Democratic. 

The kind of conservatism found in the Intermountain West is awfully different that that found in the Southeast.  The “conservatism” found in the West is much more libertarian and tends to have much less emphasis on social issues.  In Idaho, Montana, and Wyoming the general attitude towards the federal government is “STAY AWAY”! But keep shelling out dough for water projects, military bases, ag and mining subsidies, and leasing federal land to business for well below market value.[/b] 

Corrected.