The nonpartisan, nonprofit National Institute on Money in Politics (NIMP) promotes an accountable democracy by compiling comprehensive campaign-donor, lobbyist, and other information from government disclosure agencies nationwide and making it freely available at FollowTheMoney.org.
The Institute researches and archives a 50-state federal/state database of contributions documenting $100+ billion, plus more than 2 million state lobbyist-client relationships that are registered annually. Recent expansions include selected local-level data, collecting independent spending reports for federal campaigns and in 31 states, and lobbying spending in 20 states.
Has a REST API: https://www.followthemoney.org/our-data/apis
You have to register for a free API key to use it. By default, you can pull up to 1000 records per year.
How to find your API key:
Corporation Wiki exists to provide corporate transparency and historical data on companies. This allows officers to be held accountable for the actions they take through their corporations. Imagine if anybody could hide behind a fictitious name and say and do anything that they wanted without concern of discovery. If the internet provided the same level of transparency, imagine how many less trolls there would be lurking in the comment sections of websites around the world (We're talking to you, youtube).
People around the world rely on us to help validate that someone is as awesome as they say they are. Others rely on us to help them discover fraud and malice. It's a check-and-balance. As long as good and evil exist, so will we.
Where the candidates stand on the matters that matter.
A website that correlates politicians, the resolutions and bills they vote for (and how), who contributed to their campaigns, and how much was contributed.
LittleSis is a site and mapping engine that data mines contributions, payments, and influence between political figures, lobbyists, contributions, and the very wealthy. Good for finding out who owns which politician, or which ones to "invest" in.
REST API: https://littlesis.org/api