(Tableau Public is an AMAZING and free tool for analyzing data. I'm a big fan of both the commercial version of their software, and this free version.)
This data visualization shows how every state voted in every Presidential election in the USA since 1916. More blue = democrat, more red = republican.
This is utterly fascinating and beautiful to look at, too.
Then to think about how history changed, and how that reflected on the White House (can you say "Southern Strategy" everyone?), this chart is vivid reminder that the Republicans are strategists and the Democrats are hapless do-gooders. (My interpretation. ;-)