The Lugar Center and Georgetown University’s McCourt School Unveil New Bipartisan Index Rankings of All U.S. Senators

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December 15, 2015

Media Contacts:

Lauren Mullins

Betsy Holahan

WASHINGTON, DC — The Lugar Center, led by former U.S. Senator Richard Lugar, and the McCourt School of Public Policy today jointly released their new Bipartisan Index rankings of all U.S. Senators who have served in Congress since 1993.  The non-partisan tool indicates the degree to which Senators work across party lines.

“This new data illustrates the changing nature of the Congress and helps explain why it has become so dysfunctional in recent years,” said Lugar Center President Richard G. Lugar, who served for 36 years as a Republican Senator from Indiana. “But it also shows that some lawmakers with strong ideological views can nonetheless find common ground with members of the other party.”

The rankings, based on bill sponsorship and co-sponsorship, follow the initial Bipartisan Index data for the 113th Congress (2013-14), which was one of the most partisan of the past 20 years, and provide historical context for the increased partisanship in Congress over the past two decades.

“We hope the Bipartisan Index reminds lawmakers that you can be bipartisan while being true to your conservative or progressive ideologies,” said Edward Montgomery, dean of the McCourt School. “Our society faces significant challenges both domestically and abroad. Now, more than ever, we need our lawmakers to work together to get things done.”

The new data allow voters to see over time how willing their Senators have been to work across party lines.  Based on the scores, former Sen. Lincoln Chafee (R, R.I.) ranks as the most bipartisan while Sen. Susan Collins (R, Me.) is the most bipartisan current senator and second overall. 

At the other end of the list, former Sen. Jim DeMint (R., S.C.) ranks as the least bipartisan, while the lowest-ranked current senator is Tim Scott (R, S.C.), who is second from the bottom.

The Bipartisan Index measures how often a member of Congress introduces bills that succeed in attracting co-sponsors from members of the other party, and how often they in turn co-sponsor a bill introduced from across the aisle.  The Index is based on a formula applied uniformly to all members. No subjective judgments are made about individual members or bills. The Index will serve as a critical resource for voters and the media and, its sponsors hope, encourage lawmakers to be more bipartisan when writing or co-sponsoring legislation.

The rankings for the 113th Congress, released in May, covered both the House and the Senate. Today’s data include the 11 Congresses between 1993 and 2014. They include rankings and scores for all Senators who served for at least 10 months during that period. Rankings for the House of Representatives will be released in 2016.

The new data also shed more light on some of the current candidates for President. The initial Bipartisan Index included the two-year scores for the primary candidates who served in the 113th Congress—Democratic Sen. Bernie Sanders of Vermont and Republican Sens. Ted Cruz of Texas, Lindsey Graham of South Carolina, Rand Paul of Kentucky, and Marco Rubio of Florida. The new data gives composite Senate rankings for them, and offers new rankings for former Democratic Sen. Hillary Clinton and former Republican Sen. Rick Santorum who served in previous Congresses.  President Obama, a former senator from Illinois, and Vice President Biden, a former senator from Delaware, also are ranked for their Senate service during the period.


About The Lugar Center:

Under the leadership of former U.S. Senator Richard Lugar, the non-profit Lugar Center is a platform for informed debate and analysis of global issues, including nonproliferation of weapons of mass destruction, global food security, foreign assistance effectiveness and global development, energy security, and enhancing bipartisan governance.

About the McCourt School of Public Policy:

Founded in 1996 as the Georgetown Public Policy Institute, the McCourt School of Public Policy at Georgetown University is a top-ranked graduate school located at the center of the policy world in Washington, D.C. Our mission is to give our students the rigorous quantitative and analytic skills needed to design, implement and evaluate smart policies and to conduct policy research and recommend effective solutions on today’s most critical topics.