I found this election map a while back and promptly lost the link to it, and now I've finally found it again. It's deliberately responding to the impression given by the red-blue maps that abound that there are Republican states and Democrat states. The idea here is that certain regions of the country (not necessarily along state lines, often splitting states) tend to vote in certain ways. This group has identified 10 regions with slightly different voting tendencies from each other, with some excellent analysis of how each region has voted in past elections and even some advice to both parties about what strategies might help in 2004.
I do think the red-blue maps reveal something about a divided country, the same thing revealed by the book-purchasing map showing that people who buy political books only read one side. This explains why so many liberals don't understand why anyone would like George Bush and why so many conservatives don't understand why anyone wouldn't like him. Many of them probably don't even know anyone who has the opposite reaction they have.
Still, this balanced look at what's really going on shows that the red and blue states and regions aren't monolithic and that there's a lot more complexity to the ways in which these tendencies will manifest themselves (e.g. out west and in NH the support for Republicans is largely libertarian, whereas social conservatives dominate in parts, but only certain parts, of the south). I found it fascinating to read about the voting trends of part elections in the way they did it. They collected data according to counties, drawing lines where the tendencies reflect changes in voter tendencies.