Although Politicians often pledge to “work across the aisle” when campaigning for office, bipartisanship remains a rare occurrence in state and federal government. How well do elected officials actually follow through on their promises to work with members of the opposite party? We turned to the Lugar Center’s Bipartisanship Index to find out.

The Lugar Center’s index takes into account bill sponsorship and co-sponsorship data to objectively measure the bipartisan tendencies. They use sponsorship data because it represents “carefully considered declarations of where a legislator stands on an issue” whereas votes are often dependent on a variety of other factors. We geocoded the index to map the partisan behavior of legislators from each state.


The darker red the state, the more partisan the state’s members of Congress are. In the lead for the most partisan states (and districts) are Rhode Island, South Carolina, and Washington, D.C..

According to Lugar Center data, Alaska, Maine, and West Virginia are represented by the individuals most willing to work with members of the opposite party - something that Crowdpac scores confirm. Alaska’s Senators Lisa Murkowski and Daniel Sullivan with scores of 2.8C and a 4.6 C respectively, are relatively moderate conservatives. Maine has a mixed senatorial duo of Republican Susan Collins, a squishy 1.2C, and Independent Angus King with a Crowdpac score of 4.3L. West Virginia is also represented by one Democrat and one Republican- Joe Manchin at 1.6L and Shelley Capito at 3.7C. According to the data, these moderate, even ideologically opposed legislators are more willing to compromise in Congress.

Lastly, it is worth noting that the states that are most neutral (neither partisan nor bipartisan) include many of America’s key battleground states. Nevada, New Hampshire, Virginia, and North Carolina are all among the partisanship-neutral states. Perhaps the purple state legislators aim to mirror their moderate electorates.

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