Crowdpac, a nonpartisan firm dedicated to political data analysis, used federal campaign-contribution records dating to 1980 to estimate where various officials and donors fall on the political spectrum.

It scored individual donors as being more liberal or conservative based on which candidates they gave to.

Crowdpac CEO and cofounder Steve Hilton told Business Insider this donation data "is the heart of the Crowdpac data model" because its "research shows that campaign contributions are the best predictor of how a candidate will behave in office."

Hilton explained that Crowdpac's main goal is to provide people "good objective, nonpartisan information about the candidates on their ballot in a simple form that they can understand."

The company believes this will help "boost the number of small donors and reduce the influence of big money in politics."

As part of its analysis, Crowdpac is able to break down where various professions fall on the political spectrum. It provided that data to Business Insider.

Here's a summary of its findings:

That basic summary shows the average ideology scores for each profession. But the "purple" professions that appear in the middle of the spectrum aren't really bipartisan. They're actually extremely polarized: Rather than having a large number of donors with middle of the road politics, they're largely split, with a big liberal group on one side and a similarly sized large conservative group on the other.

These divides can be seen in the following charts, which were provided to Business Insider by Crowdpac and show the number of donors with each ideology score in each profession.

Liberal Professions

Some of the professional groups have clear liberal leanings. People who work in the news media are almost exclusively donors to liberal candidates:

Donors in the entertainment industry are similarly liberal:

Academics also tend to give to liberal candidates:

The tech industry has a decidedly liberal bent as well:

The pharmaceutical industry has some more conservative donors, but the bulk are quite liberal:

Lawyers are a bit more mixed across the spectrum, but tilt liberal:

Conservative Professions

Other industries have more right-leaning donation patterns. Farmers are largely conservative:

Donors from the building and construction industries have a similar conservative lean:

Mining is also a conservative industry:

The related field of oil, gas, and coal is largely conservative too, albeit with a few more liberal donors than mining:

The tobacco industry leans to the right as well:

Real estate is more of a mixed bag, with a decent number of liberal donors, but a larger number of conservatives:

Banking and finance follows a similar pattern:

Polarized Professions

The rest of the industries reviewed by Crowdpac show a pattern of having a large number of donors from both ends of the political spectrum.

While real estate and finance had a solid conservative lean, donors from the world of hedge funds and private capital split along ideological lines, with large groups on both sides of the spectrum:

Lobbyists are, perhaps unsurprisingly considering their role in the political system, similarly split:

Finally, automotive manufacturers and dealers also have big polarized spikes at opposite ends of the spectrum, although there are more liberals in the group than conservatives: