There is apparently a momentum emerging around opening up publicly relevant datasets:

The nonpartisan watchdog group OpenSecrets, Center for Responsive Politics, announced the release of some 200 million data records from its archive "to the hands of citizens, activists, journalists and anyone else interested in following the money in U.S. politics." OpenSecrets.org also offers a number of APIs (Application Programming Interfaces) to give users direct access via web programming to their data repository. Users can also share CRP data using OpenSecrets.org's widgets, which can be placed easily on any website or blog. New widgets for the 2010 election cycle are in development.

All the data can be downloaded in bulk here [opensecrets.org] and consists of:
- Campaign Finance: 195 million records dating to the 1989-1990 election cycle, tracking campaign fundraising and spending by candidates for federal office, as well as political parties and political action committees.

- Lobbying: 3.5 million records on federal lobbyists, their clients, their fees and the issues they reported working on, dating to 1998.

- Personal Finances: Reports from members of Congress and the executive branch that detail their personal assets, liabilities and transactions in 2004 through 2007.

- 527 Organizations: Electronically filed financial records beginning in the 2004 election cycle for the shadowy issue-advocacy groups known as 527s, which can raise unlimited sums of money from corporations, labor unions and individuals.

Via IA

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