Sunlight Foundation
The Sunlight Foundation is a 501(c)(3) nonpartisan nonprofit organization[3] that was founded in April 2006 with a goal of increasing transparency and accountability in the United States Congress, the executive branch, and in state and local governments. The foundation's primary focus is the role of money in politics,[4] and advocates for policy changes to build a more open government, builds technological tools to increase the participation of citizens in government, and conducts original reporting on accountability and other open government issues.
Source Wikipedia http://en.wikipedia.org/wiki/Sunlight_Foundation
When it comes to writing big checks to favored candidates and causes, unions last year seemed to be taking greater advantage of the landmark Citizens United decision than corporations.
A Sunlight analysis of groups and individuals who wrote checks of $10,000 or more to super PACs and other political committees that report to the FEC revealed big labor bested big business in 2013 by better than 2-to-1.