Robin M. let us know about an image at Mother Jones that apportions out seats in the Senate and House of Representatives not by state or party, but by financial backers. Dave Gilson asks, “What if members of Congress were seated not by party but according to the industries which gave them the most money over their entire careers?” Here’s the methodology used to create the charts:

The Congressional seating chart is based on which industry has given the most to each member of Congress over his or her career. This means that members are seated according to the industry that has given a plurality of donations. For example, a member who received 20% of her donations from financial firms and 19% from unions would be seated in the finance, insurance, and real estate bloc.

Corporate donations include money given by companies’ employees and political action committees, unless noted otherwise. Counting employees as corporate donors isn’t perfect: You may not give to a candidate with your employer’s interests in mind. Yet excluding individual contributions would overlook “bundled” gifts from a company’s employees as well as gifts from executives and their families.

Clearly that doesn’t provide a perfect measure of where campaign money comes from, but it does give a sense of the major players. Here’s the result for the Senate, where finance/insurance/real estate wins the day:

And here we have the House, where labor unions play a much larger role:

Obviously the real impact of some of these industries will be greater than what shows up here, since many will be major, but not the single largest, source of funds to lots of candidates. And we don’t know the actual value of the donations for those seats; perhaps the transportation industry, say,contributes to fewer candidates but spent much more on them than labor did on average per campaign. Knowing who the biggest single donor to a politician is doesn’t necessarily tell us a lot about how beholden the official might feel to that industry. And it doesn’t include any of the indirect spending groups do on “issue ads” that don’t clearly endorse a particular candidate, or to the Democratic or Republican campaign committees overall rather than an individual.

Nonetheless, I think it’s a useful graphic for highlighting who some of the big players are.

UPDATE: Reader A.D. Pask-Hughes asks…well, “so what?” Fair question, especially given that I outline a number of methodological flaws. What struck me as interesting:

1) The differences in primary donors between the Senate and the House, particularly that labor is so much more visible in the House

2) The relatively low profile (from this measure) of defense


3) The difficulties in accurately measuring “influence” in Congress.