Sen. Susan Collins, R-Maine, speaks during a Senate Appropriations Committee hearing Wednesday on Capitol Hill in Washington. Credit: Bill O'Leary / The Washington Post via AP

U.S. Sen. Susan Collins on Monday was ranked as the nation’s most bipartisan senator for the eighth straight year.

That comes after Collins won a historic fifth term in the U.S. Senate after a nationally targeted race and her approval rating slumped after four years under former Republican President Donald Trump.

Collins received the highest bipartisan score for the 116th Congress in the Lugar Center and Georgetown University McCourt School of Public Policy’s Bipartisan Index. Maine’s junior senator, independent Angus King, ranked as 37th on the index. That’s up from 45th last year.

In the U.S. House, U.S. Rep. Chellie Pingree, a Democrat from the 1st District, ranked 125th, down from 107th the year before, while U.S. Rep. Jared Golden, a Democrat from the 2nd District, ranked 77th, up from 117th.

Ranking is based on how often lawmakers co-sponsor legislation from those in a different party and their bills attract co-sponsors from across the aisle. Dan Miller, policy director at the Lugar Center, praised Collins as an “unrivaled leader” for bipartisanship in Washington.

“Year in, year out, no Senator has matched her devotion to constructing bipartisan legislation in the interest of getting things done for her constituents and our country,” Miller said Monday.

Collins, who has served in the U.S. Senate since 1997 and the only New England Republican serving in Washington, also ranks as the second-most bipartisan senator over a 26-year period, behind only Lincoln Chafee, a Republican who represented Rhode Island in Washington from 1999 to 2013. After leaving Washington, Chafee ran as an independent for governor in Rhode Island and later joined the Democratic Party.

Collins has long touted her willingness to work across the aisle, drawing at times scorn and praise from Republicans and Democrats alike. In recent years, Collins most prominently bucked her party when she cast one of the three deciding votes that sunk the Republican-led effort to repeal the Affordable Care Act in 2017.

But she joined her Republican colleagues that year to confirm Neil Gorsuch to the U.S. Supreme Court and to pass a tax bill. She drew sharp criticism from Democrats in 2018 over her vote to confirm Brett Kavanaugh to the nation’s top court, and then later drew the ire of conservatives for voting against confirming Trump’s third high court nominee, Amy Coney Barrett.

In February, Collins broke with Republican ranks when she voted to convict Trump for his role in the deadly Jan. 6 riot on Capitol Hill, where a pro-Trump mob sought to prevent the certification of Democratic President Joe Biden’s Electoral College win. Only six other Republican senators voted to convict Trump.

Many of them faced public rebukes and censures from their home state parties. The Maine Republican Party overwhelmingly voted against censuring Collins despite the outcry from rank-and-file conservatives over her conviction vote.

In a Monday statement, Collins said that bipartisan solutions provide “the best answers” to the challenges the nation faces, saying that “spirit of collaboration is needed now more than ever as we emerge from a pandemic unprecedented in modern times.”

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