Colorado was home last year to one of the most bipartisan members of Congress and one of the least bipartisan lawmakers, according to an index released last week by the nonpartisan Lugar Center and the McCourt School of Public Policy at Georgetown University.

Finishing in 11th place out of 435 House members, U.S. Rep. Jason Crow, a Centennial Democrat, led Colorado’s delegation on the list, while his Republican colleague from Silt, U.S. Rep.Lauren Boebert, landed near the bottom, just two spots above the lowest-ranking House member in the country.

Democratic U.S. Sen. Michael Bennet came in 29th in the list of senators, the annual report found – still in bipartisan territory, according to a complicated formula the academic center uses to measure how much lawmakers work across party lines on legislation.

Its authors said this year’s study showed a “sharp drop in bipartisanship” in both chambers compared to previous results, especially among Republicans.

“Many observers speculated how well members of Congress would work together in the aftermath of the January 6, 2021, attack on the Capitol,” said Dan Diller, the Lugar Center’s policy director, in a release. “Regrettably, the new 2021 Bipartisan Index scores offer strong quantitative evidence that bipartisanship at the individual member level plummeted last year.”

Crow scored 1.52455 on the center’s scale, putting the second-term lawmaker in the top 2% for bipartisanship for the first year of the 117th Congress.

The ranking marks a substantial jump from the previous index, which found Crow in 63rd place for the 2019-2020 period with a score of 1.01193.

“At a time of deep partisanship and division in our country, I have made it my priority to get results for Coloradans,” Crow told Colorado Politics in a statement. “I’m proud to work on behalf of those who elected me and I remain deeply committed to doing the work of lowering costs for hardworking families, helping our small businesses, and getting our economy back up and running as we recover from the pandemic.”

The score measures how often bills introduced by lawmakers attracts co-sponsors from across the aisle and how often they sign on to bills introduced by members of the other party. It factors in historic data but doesn’t count non-binding resolutions or ceremonial bills. Scores in positive territory reflect bipartisan behavior.

Last year’s top finisher among Colorado House members, Democrat Joe Neguse of Lafayette, came in 58th in the new rankings with a score of 0.34273, dropping from his 41st-place finish in the 116th Congress with a 1.26380 score.

Pennsylvania Republican Brian Fitzpatrick topped the House index with a score of 4.00118, followed by New Jersey Democrat Josh Gottheimer with 2.74575.

Boebert finished in 433rd place with a score of -2.03033, just behind Arizona Republican Andy Biggs with -1.95534 and one place ahead of Georgia Republican Marjorie Taylor Greene, who scored -2.05913. Only Illinois Republican Mary Miller ranked lower, with a -2.09076 score.

None of Colorado’s other House members had scores above zero. Democrat Ed Perlmutter was ranked 128th with a -0.11066 score, Republican Ken Buck came in at 175th with a -0.34091 score, Democrat Diana DeGette finished in 184th place with a -0.37872 score, and Republican Doug Lamborn came in 390th with a -1.39444 score.

Bennet’s score of 0.33242 put the two-term senator behind 28 other senators with higher bipartisanship scores, led by New Hampshire Democrat Maggie Hassan, whose 2.84366 was enough to bump perennial top-finisher Susan Collins, the Maine Republican, who scored 2.21384 in this year’s study.  

Democrat John Hickenlooper, Colorado’s junior senator, came in 62nd in his first year in office with a -0.47394 score.

The Republican lawmaker Hickenlooper replaced, former U.S. Sen. Cory Gardner, routinely finished near the top of the Lugar Center’s index, including coming in fourth overall in the previous Congress, in session from 2019-2020, and finishing in fifth place for the two-year period before that.

The index, in its 30th year, has its detractors, including some who maintain its content-neutral formula papers over starkly partisan behavior that undermines the study’s stated objectives, but its sponsors counter that they’re measuring something important.

“The Bipartisan Index provides an important indicator of the state of congressional collaboration,” Marcia Cancian, dean of the McCourt School of Public Policy, said in a statement. “While it is disappointing that collaboration has declined over the last year, I am encouraged by the lawmakers who are steadfastly committed to working across differences to advance the common good.”