That urban/rural split runs even more precisely. I got such a map for Monroe county in NY (around Rochester) showing votes by electoral district, and the division was pronounced even there: only distinctly urban areas went to Gore (who carried the county), while the rest of the county went to Bush.
Urban = dependent = Gore.
Rural = independent = Bush.
With such a clear division throughout the country, things will likely get very interesting. Perhaps the rural folks will discover this, and cause the urbanites to discover the hard way that their supplies don't magically appear in stores.
