Somewhat of a milestone in political games, since it was commissioned officially by the Howard Dean campaign for his run in the 2004 Democratic primary. Has a map-level strategic view in which you place supporters, and once you place a supporter, goes into a short real-time segment where you try to wave your campaign sign at people. There were initially some social effects, with the map changing colors based on the level of Dean support in various regions created by other players of the game, plus even some instant-messaging integration, though the IM integration has since been disabled, and the social effects are hard to see since few people still play the game. The main aim of the game seems to have been to raise some vague awareness about how the caucus system works, plus just create some buzz.
The creators give a detailed retrospective account in this essay.