I came across this demographic today. People in the Mid-West and the North West of the United States drink 'pop'. People who live in the South drink 'coke' and people on the West and East coasts drink 'soda'. Never having spent much time in the U.S. myself I wondered what this might mean. Of course, we have Tocqueville's division of the states into Northern democratic and Southern aristocratic. Then I thought of Orlando Patterson's view that the East and West Coasts are cosmopolitan/ecumenical (roughly - they value irreverent cultural medley) but the coasts sandwich a big space where people are multicultural (roughly - they are respectful of cultural distinction). What's that got to do with fizzy drinks, though?
And there is a large cluster of 'soda' drinkers half way down the mississippi...