The Maine Republican, known for her fierce independence, lamented that the Senate has evolved into something akin to a parliamentary system in which members vote in party blocs, promoting corrosive partisanship that has led only to gridlock.

“I’m so passionate about changing the tenor in Congress because I’ve seen that it can be different,” she said. “It hasn’t always been this way. And it absolutely does not have to be this way.”

Snowe shocked the political establishment in late February when she abruptly ended her bid for a fourth term, which she would have easily won, citing partisan gridlock.

Speaking from the Senate floor in Washington, D.C., Snowe took time Wednesday to thank the people of Maine for placing their trust with her during 34 years in Congress, including three terms in the Senate. Snowe, a Greek-American who was orphaned at age 9 and ran for her late husband’s legislative seat at age 26 after he died in a car crash, went on to become the third-longest-serving woman in congressional history.

Snowe said she inherited a legacy of bipartisanship and independence from the late Sen. Margaret Chase Smith, who is remembered for her “Declaration of Conscience” speech attacking McCarthyism.

On Thursday, Snowe focused on something that she found to be important more than 60 years later — a lack of civility and excessive partisanship that she says prevent the Senate from accomplishing the Founding Fathers’ ideals.

She repeatedly pointed to examples of senators working together in the past.

“Our problems are not insurmountable, if we refuse to be intractable,” she said. “It is not about what’s in the best interests of a single political party but what’s in the best interests of our country.”

She also encouraged her colleagues to tread delicately as they consider changing rules on filibusters, a tactic used to keep a bill from coming up for a floor vote. Senate Majority Leader Harry Reid, D-Nev., has said he may change the rules on the first day of the new Congress in January, allowing a simple majority to overcome a filibuster. Sixty votes are currently required.

Part of what makes the Senate unique is its “balance between accommodation of the minority and primacy of the majority,” Snowe said. “Suppression of the ability to debate and shape legislation is tantamount to silencing millions of voices and ideas, which are critical to developing the best possible solutions.”

Snowe said she’s not leaving the Senate because she’s ceased believing in it. Instead, she said, she wants to work from outside to encourage bipartisanship and consensus, adhering to the founding precepts of civility and compromise over partisanship and division.

Snowe has started a political action committee, called Olympia’s List, that supports candidates and elected officials who believe in consensus-building.