Indiana Sen. Joe Donnelly 2nd-most bipartisan senator since 1993, study says

Sen. Joe Donnelly,  D-Ind., is the second-most bipartisan senator who has served in congress since 1993, according to a Georgetown University study.

The study, from the university's McCourt School of Public Policy and Richard G. Lugar Center, shows that only Lincoln Chafee, a former Republican senator and governor of Rhode Island, was more bipartisan during his Senate tenure than Donnelly has been. Chafee was a Republican until he switched to the Democratic Party in 2007, running as a Democratic presidential candidate in 2016. 

The study also says Donnelly was the second-most bipartisan senator of the 114th Congress, behind only Susan Collins, R-Maine. Collins is considered a moderate Republican; she holds a liberal stance on abortion but a conservative stance on most other social issues. She voted in favor of the Republican tax reform bill Dec. 3.

Donnelly was targeted as a Democrat who could have been convinced to support the Republican tax reform bill that passed the Senate Dec. 3. Donnelly ended up voting against the bill, saying it kept a tax loophole that would "mean many Hoosier workers pay a higher tax rate than Wall Street hedge fund managers."

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Donnelly's Senate seat is up for grabs in November 2018, and it is a hotly contested race. Republicans Luke Messer and Todd Rokita are vying to challenge Donnelly, who will run for a second term, for his seat. 

The Center for Effective Lawmaking in August also called Donnelly the least effective Democrat in the Senate. 

The Lugar Center study aims to quantify congressional members' bipartisan behavior, and bases its rankings off bill sponsorship and co-sponsorship. So a congressperson who introduces bills with more bipartisan sponsors would rank as more bipartisan. And similarly, if a congressperson co-sponsors a bill created by a congressperson from a different party, that person would again rank as more bipartisan. 

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Here's where other Indiana senators ranked on the list:

• Richard Lugar (R) — 26
• Evan Bayh (D) — 66
• Dan Coats (R) — 228

You can view the study and methodology in its entirety here.

Andrew Clark is a digital producer for IndyStar. Follow him on Twitter @Clarky_Tweets.