Shortly after Election Day, we created a chart that showed the spending by outside groups in a number of key Senate races. It's here, and it's useful information -- particularly in light of the increased percentage of federal election spending which never touches an actual campaign (or party) organization.

There's still plenty of money going to campaigns, of course. The Center for Reponsive Politics tracks campaign reports to the Federal Election Commission that detail contributions. If the contribution is from an individual, the campaign is required to find out the person's occupation (including "homemaker" or "retired," as needed). The real value in what CRP does is that it then analyzes that data, figuring out which individuals work for which companies and which companies belong to which industries. Meaning that for every candidate, it can estimate how much money came from PACs or people associated with finance, or energy, or mining, or whatever.

We took that data and figured out the 25 most generous industries, then broke down contributions to the Democrat and Republican in each of 10 races. Before we explain our analysis. Here's the chart that results.

You'll notice that industry support was often mixed between parties. People or PACs from the real estate industry, for example, gave to every candidate. Lawyers gave more heavily to Democrats, usually unsuccessfully; people from the investment industry usually gave more to Republicans, with more success.

The oil and gas industry didn't give as much as some of the others that are listed, but it notably gave far more than people or PACs from environmental groups. ("Environment" is sixth from the bottom.) Oil and gas gave a lot to one prominent loser: Sen. Mary Landrieu (D-La.), who just happens to be the outgoing chairman of the Senate energy committee.

This chart is good for comparing how much support candidates saw from each industry. But it doesn't tell us much about how the industries themselves fared.

When you look at contributions to campaigns, you can see which had the most luck. Namely, as noted above, securities and investment firms. But you can also see how much better they did than lawyers. Oil and gas were net winners; the environmental movement, net losers. Women's issues, whose "industry" (it's not a precise term, obviously) gave a lot to Democrats, but only did well in New Hampshire.

There's a long-standing assumption that it is the campaign contributions that spur loyalty from elected officials. There's not much evidence of that, though donations probably do help open doors.

One reason that there's not a bright line from donor to political action: There are a lot of donors who are smart enough to give to candidates from both parties. Only tightly defined or politically dominant industries can afford to play favorites with any regularity. And when they do -- as in the case with women's groups in 2014 -- it can mean a bad election.