MapLight's Core Work

Data Sets       Analysis       Custom Research       Projects

MapLight has three key strengths that, collectively, are not possessed by any other transparency or accountability organization:

  1. We possess a unique, proprietary data set of companies’ and organizations’ support for and opposition to bills in Congress, kept continually up-to-date by MapLight researchers.
  2. We combine multiple data sets in a large-scale way to systematically uncover connections between political inputs and political outputs – i.e. the impact of special interest influence.
  3. We proactively work to ensure our data is used by accountability actors such as journalists and nonprofit groups to make a real-world impact on public accountability. Our focus on and systems for reaching the public with our data ensure that our data is utilized for accountability purposes instead of just serving academic or general informational purposes.

Money and Politics Data Set

Only MapLight produces a unique database combining lawmakers’ votes, groups supporting and opposing legislation, and campaign contributions—a database specifically developed to serve increased public accountability. A portion of the data in MapLight’s database is uniquely collected by us and includes information about the groups supporting and opposing legislation.

MapLight's Money and Politics Data Set is an easy-to-access, downloadable database featuring MapLight-enhanced Federal Elections Commission campaign finance data and available for free public use. The data set includes all federal contributions, independent expenditures, and candidate and committee totals, updated regularly with the most current data from the FEC. Citizens, journalists, and programmers can now view, search, sort, filter, and visualize (with charts, line graphs, bar graphs, scatter plots, and timelines) federal campaign contributions using Google Fusion Tables.

Our data can also be merged with outside databases, and visualizations can be easily embedded into blogs, media sites, and more. We are excited to see what the web community builds with this continually-updated public data. The complete MapLight Money and Politics Data Set can also be downloaded or accessed via API for free public use in websites, widgets, and apps.

Our support and opposition database includes which interest groups, companies, and organizations support and oppose key bills in Congress. For each bill, our in-house research team uses public record sources, like Congressional hearing testimony, news databases, and trade associations’ websites, to determine a bill’s supporters and opponents.

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We work alongside numerous groups who share an interest in transparency and/or political accountability. Most of these groups focus exclusively on tracking or providing public access to various forms of political inputs, such as data sets of campaign contributions or lobbying. Only MapLight is focused on connecting these political inputs to political outputs, such as the outcome of a particular vote, to systematically uncover and publicize instances of special interest influence.

Making these connections is integral to successful public accountability work. In order to mobilize the public to press for accountability around a particular instance of corruption or political influence, it is necessary to draw the connection between the influence and its impact.

Read original MapLight content based on our analysis and findings here.

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Custom Research

MapLight develops our data, tools, and research services specifically to help journalists and nonprofit groups have public accountability impact. We offer custom research at no cost, provided that the resulting data is used for content that is free to the public.

In the past year alone, MapLight’s research and communications teams fielded a total of 175 requests for custom money and politics data from journalists, nonprofit advocates, activist groups, and others.

Our transparency tools and research services continue to be used by an ever-wider network of accountability actors to craft bold, urgent calls for change and reform.

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Bill Research

MapLight's Bill Research tool combines bill text and legislative voting records with campaign contributions, making key money and politics information easily accessible with the click of a mouse. Users can apply filters to the data to sort by legislators' political affiliation, interest groups, date range, and types of contributions.

Get started here.

Bill Research

Voter's Edge

Voter's Edge is an ever-expanding online voter guide, currently providing nonpartisan, comprehensive information for ballot measures in eight states, nine cities, and six counties. Complete with summaries, impact analyses, funding information, editorials, news articles, campaign ads, and more for each ballot measure, plus daily updates reflecting breaking developments, Voter’s Edge is a central access point to previously disconnected information, making it easier than ever to decide how to vote.

Go to Voter's Edge to get informed about state and local level ballot initiatives.

Voter's Edge

Influence Tracker

MapLight teamed up with to launch our Influence Tracker widget, which ranks federal candidates by their relative fundraising prowess, revealing the total number of dollars raised by each contender in the past two years and their top 10 contributors.

influence tracker

Data Visualizations

In a continuing collaboration with Tableau Software, MapLight produces interactive data visualizations, making funding information easy to see and share while providing powerful customization tools for journalists and others seeking more. See them all here.

MapLight Data Visualizations - 5 million dollar club, top funded Super PACs MapLight Data Visualizations - Leaders of the Super PAC

Politicash Mobile Phone App

MapLight put the power to hold politicians accountable literally in citizens’ hands this election season with our mobile app, Politicash 2012. Freely available for iOS and Android, the app tracked money flowing into the presidential race, making it easier than ever to know exactly who’s funding the candidates, including the shadowy sums going into the campaigns of their affiliated super PACs.

Politicash App Politicash App - money raised by Obama and Romney Politicash App - Romney's top supporters

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Learn more about the impact MapLight has had so far.