Susan Collins Tops 'Most Bipartisan' in Senate Lugar Index

Sen. Susan Collins, R-Maine, is at the top of the Lugar Bipartisan Index, a listing that grades members of the House and Senate according to how well they work with each other, while Vermont Independent Sen. Bernie Sanders, who mounted a race for the Democratic presidential race in 2016, placed last.

According to The Lugar Center, the index was created to "fill a hole" in the information that is usually made public about congressional members' actions.

Overall, with the exception of one senator, Republicans took the top 10 spots in the rankings:

1. Sen. Susan Collins, R-Maine;
2. Sen. Rob Portman, R-Ohio;
3. Sen. Shelley Capito, R-W.Va.;
4. Sen. Joe Donnelly, D-Ind.;
5. Sen. Dean Heller, R-Nev.;
6. Sen. Lindsey Graham, R-S.C.;
7. Sen. Chuck Grassley, R-Iowa;
8. Sen. Cory Gardner, R-Colo.;
9. Sen. Todd Young, R-Ind.;
10. Sen. Marco Rubio, R-Fla.

The Lugar Center is a think tank founded by former Sen. Richard Lugar, R-Ind., and Georgetown University's McCourt School of Public Policy, and produces the non-partisan ranking of how often each congressional member works across party lines.

There are several studies, rankings and indexes about lawmakers' performances, according to the center, but those are usually based on partisan or special-interest standards.

The Bipartisan Index instead focuses on bill sponsorships and co-sponsorships, as they allow the organization to determine a "highly objective measure" of lawmakers' partisan and bipartisan behavior.

It also measures how often a member of Congress co-sponsors a bill introduced by the opposite party, and how often that member's bills attract co-sponsors from the other side of the aisle.

Lawmakers who score above zero are deemed to have a good score. Collins' score total is 3.15, while Sanders came in at negative 2.11.

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