MAPLight is a Berkeley non-profit dedicated to illuminating the connections between money and politics. The Contribution Map is an interactive visualization that displays campaign contributions by geographical area on a national map. The interface allows users to filter contributions by interest group and/or politician, to see side-by-side maps showing the differences between political parties, and to export a custom map as an image or an embeddable widget.
I built the map and interface in Adobe Flex, using the Flare visualization library and a Model/View/Controller/Service architecture. The MAPLight.org site runs on Drupal, and the implementation included a custom Drupal module to support the visualization.