Nationally, the  Howard Dean presidential campaign pioneered the use of the Net for grassroots campaigning, involving ordinary people in the election process. The Net proved to be an effective tool for organization and fundraising. However, this campaign didn’t quite reach critical mass, perhaps because there weren’t enough Americans with high-speed Internet connections at the time.
(I think I met some Drupal folks who were involved in the Dean effort back then, but can’t remember who they were. If it’s you, please comment here and tell us about the experience.)