Alex Brandon/AP

Some superPAC donors are hiding from public scrutiny. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Invitations to fundraisers for members of Congress frequently mention which committees they serve on. Sunlight Foundation/Political Party Time hide caption

itoggle caption Sunlight Foundation/Political Party Time

"I think most Americans would be shocked..." - Sen. Dick Durbin. Brendan Smialowski/Getty Images hide caption

itoggle caption Brendan Smialowski/Getty Images

Jack Abramoff in 2004. He's the one on the right. Dennis Cook/AP hide caption

itoggle caption Dennis Cook/AP