A 16-year-old programmer, Nicholas Rubin, has developed a browser plugin that, when you mouse-over the name of a US lawmaker, will serve up a list of which parties have donated to their campaign funds, and the quantities.
Greenhouse (geddit?) is currently available for Chrome and Safari, with Firefox coming at some point in the future – although our lawyers have (probably) asked us to point out that the data is from the 2012 elections, so they may not be entirely up to date but he does have plans to update it in the future.
From the Greenhouse site:
It is my hope that providing increased transparency around the amount and source of funding of our elected representatives may play a small role in educating citizens and promoting change. If you use the extension when reading about a Congressional vote on energy policy, for example, maybe you’ll discover that a sponsor of a bill has received hundreds of thousands of dollars from the oil and gas industry. Or maybe you’ll learn that the top donors to a member of Congress who opposes tort reform are lawyers and law firms. I use data from the last full election cycle (generally 2011-12 for Representatives and 2007-12 for Senators) and plan to update it as more relevant data becomes available.