(CNN) -- Democratic Sen. Kyrsten Sinema of Arizona reiterated from the Senate floor Thursday that she is not backing off her position to uphold the filibuster, less than an hour before President Joe Biden arrived on Capitol Hill to pitch Democrats on eradicating it.
She said removing the filibuster would not guarantee "that we prevent demagogues from being elected" and that getting rid of it would merely be treating the "symptom" of partisanship and not the underlying problem.
Sinema said while she continues to strongly back Democrats' elections legislation she will not support "separate actions that worsen the underlying disease of division infecting our country ... There's no need for me to restate my long-standing support for the 60-vote threshold to pass legislation."
"When one party need only negotiate with itself, policy will inextricably be pushed from the middle towards the extremes," she added, noting that she does not support that outcome, and she knows "Arizonans do not either."
Sinema's position has been consistent throughout recent negotiations on voting rights but is a fatal blow to her party as they tried to strike a unified tone in backing legislation on the issue, ahead of a self-imposed deadline Monday to act.
Sinema acknowledged some states are passing laws that make it harder for voters to access the ballot box, she acknowledged she supports civil rights groups to challenge those laws in court, and she said she will support voting rights bills coming from the House. However, she is not going to back a change to the filibuster.
Sinema argued the country needs a "sustained robust effort to defend American Democracy." She outlined some ways to do this, including supporting state and local candidates who represent the values enshrined in our Constitution and ensuring "we have a judiciary that is less lopsided in its political leanings." She also said that it is key the nation "confront and combat the rise of rampant disinformation."
Sinema drew praise from her fellow moderate in the chamber. Democratic Sen. Joe Manchin of West Virginia said he listened to Sinema's speech and that she did an "excellent job."
"I think it's the points that I've been making for an awful long time, and she has too," he said, when asked if he agrees with many of the points she made in her floor remarks.
Republicans also praised Sinema. Senate Minority Leader Mitch McConnell told CNN that her remarks were an act of "conspicuous of political courage." He added: "She saved the Senate as an institution."
This story and headline have been updated with additional developments Thursday.
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