Data source: Center for Responsive Politics
Our database includes campaign contributions given to each member of Congress. We include all contributions by donors giving $200 or more to one candidate.
Candidates and political action committees (PACs) periodically file campaign disclosure statements with the Federal Election Commission (FEC), as required by law. Each month the FEC releases new campaign filings. Our partner group, the Center for Responsive Politics (CRP), downloads this new data from the FEC and “cleans it up” to make it more useful for analysis. CRP removes duplicate transactions, standardizes company names, and categorizes each contribution according to the interest group of the donor. CRP provides this cleaned-up data to MapLight and other groups about once a month.
Campaign finance data is subject to continual updates because of amended filings, contribution refunds, and other aspects of the filing and data collection processes. As a result, data analyses and research findings on our site may change over time.
Interest Group categories
The Center for Responsive Politics tags (categorizes) each contribution according to the industry of the donor, using a taxonomy of the 400-odd interests that give money to politics. For example, contributions from Chevron’s political action committee and individual contributions from the CEO of Chevron are both tagged as Multinational Oil & Gas Producers. On our site we call these 400 categories “interest groups” or “interests.”
This interest-group categorization allows research on overall trends, such as patterns of contributions from oil interests. On the MapLight site you can view individual contributions—who gave what to whom, on what date—or you can view contributions aggregated by interest group.
These 400 interest group categories make up a three-level hierarchy, with some interest groups being part of others. For example, the interest group category Multinational Oil & Gas Producers is part of the larger category Oil & Gas, which is part of the still larger category Energy & Natural Resources. This hierarchical system makes it possible to examine both specific industries and larger trends. (Browse the interest group section of our site to see all the categories and how they fit together.)
Note: CRP has refined and expanded its categorization of interest groups over the past years. These changes are updated accordingly on our site; as a result, our data analyses and research findings may change over time.