One of the ways we can show how money influences policy in our reporting is to show where our elected officials get their campaign cash. The Federal Election Commission (fec.gov) has current searchable campaign donations listings.
This tool makes finding the exact source of reported donations easy to locate.
This does not take into account ALEC wineing and dining these candidates. Nor does it address the unlimited secret donations that can fund advertisements supporting the candidate.
But it is a start.
For those outside interests there is a reporting feature. But this requires disclosure on the outside interests reporting their donations.
Super PACs and Other Independent Expenditure Filers
Independent expenditures represent spending by individuals, groups, political committees, corporations or unions expressly advocating the election or defeat of clearly identified federal candidates. These expenditures may not be made in concert or cooperation with, or at the request or suggestion of, a candidate, the candidate's campaign or a political party.
http://fec.gov/...
As an example I have John Boehner's page here:
http://www.fec.gov/...