I cropped what you see above from an infographic that is part of GOOD magazine’s infographic section called Transparency. If you haven’t checked it out, I highly recommend it.
This was the strongest part of the graphic. It does a masterful job of elegantly illustrating a relationship both in space and time. We see that in 1998 hardly any states cared enough about gay marriage to have banned it or legalized it or had any kind of vote whatsoever. Except Alaska. Hello, Palin family. By 2004 the issue had hit the big time and gay marriage bans blanketed about half the country. The east coast showed signs of tolerance. Finally, in 2009, the east coast is holding out against a national tendency towards homophobia. Iowa surprises many by legalizing gay marriage.
What needs work
Please click through to the larger graphic. I feel that the map time series is by far the strongest part of the graphic. Perhaps because it is so elegantly simple, it was shrunk and deposited in the lower right corner.