In some ways we do. My understanding is that the political meaning of 'white people living south of the mason-dixon line' has remained far more stable (even before there was a masion-dixon line) than the definition of 'democrat' or 'republican'

But in America, it goes beyond where you live being predictive of how you vote; in America, in a real way, we give land votes; a person in a less populous state has dramatically more effect on the outcome of an election than a person in a more populous state.

(and then, of course, the obvious; we do have dramatically different laws in different states. )