Sen. Al Franken bade farewell to Capitol Hill on Thursday with a lengthy broadside against the policies of the Trump administration and a call for politicians to commit themselves to "honesty in public discourse."

The speech put to rest questions about whether Franken (D-Minn.) would follow through on his promise to resign over more than a half-dozen allegations that he had touched women inappropriately.

Until Wednesday, Franken had not announced the date he would leave the Senate, and at least two Democratic colleagues — Sens. Joe Manchin III (W.Va.) and Patrick J. Leahy (Vt.) — recently said that he should reverse his decision.

In his farewell address, Franken lamented what he described as the degradation of truth in the national political debate and the hyper-partisan environment this has produced. He will resign his seat on Jan. 2 and his successor, Minnesota Lt. Gov. Tina Smith (D), is scheduled to be sworn in on Jan. 3.

"As I leave the Senate, I have to admit that it feels like we're losing the war for truth," Franken said in his final speech on the Senate floor. "Maybe it's already lost. If that's what happens, then we have lost the ability to have the kinds of arguments that help build consensus."

As Republicans celebrated the passage of their tax plan in another part of the Capitol, Franken denounced the bill as a means of "showering corporations and wealthy donors with tax breaks and special favors."

"The Republican tax bill represents a slap in the face to those forgotten men and women" mentioned by President Trump during the 2016 campaign, he said. "I guess the president forgot about them."

Franken is one of seven lawmakers who in the past three months have resigned or decided not to run for reelection after allegations of sexual misconduct or harassment. His departure is a symbol of the wider reckoning taking place over sexual misbehavior among powerful men and the power of women's allegations in the wake of the #MeToo campaign to raise awareness about sexual harassment.

[Analysis: Could Al Franken un-resign? Sure.]

On Thursday, Franken's speech was followed by warm tributes from colleagues who praised his legacy and said they were sad to see him go.

"I'm sorry that he's leaving under these circumstances," said Senate Minority Whip Richard J. Durbin (D-Ill.). "Everyone who has ever lived has had moments they wish they could erase. . . . We all draw strength from the healing power of redemption, and we can take heart in the knowledge that tomorrow is another day."

Franken, 65, joined the Senate in July 2009 and worked hard to distance himself from his prior career as a comedian. Cultivating a reputation as a serious legislator, he emerged as a powerful voice against corporate interests in politics and one of the Democrats' most pointed and effective critics of Trump.

The two-term senator had risen as far as to be discussed as a possible candidate for president in 2020, until a woman said last month that he had grabbed her breasts while she was sleeping and forcibly kissed her in 2006. That woman, Leeann Tweeden, was followed by several others who alleged sexual misconduct by Franken.

The drumbeat of allegations proved to be too much. On Dec. 6, a wave of Senate Democrats called for Franken to step aside, and the next day he said he would resign in the coming weeks.

Franken, who apologized in the face of some of the accusations, was defiant as he made his announcement. He has denied some allegations while saying he remembered other situations differently from his accusers. He also sought to turn the tables on Trump, who faces arguably more-serious allegations of sexual misconduct.

"There is some irony in the fact that I am leaving while a man who has bragged on tape about his history of sexual assault sits in the Oval Office," Franken said in his Dec. 7 speech.

In his remarks Thursday, Franken did not address the allegations or outline his plans after leaving office. Instead, he took a comprehensive look at his political values and how they are faring under Trump.

With several references to Sen. Paul Wellstone (D-Minn.), a political mentor who died in 2002, Franken said the Trump administration and the Republican Party have "eviscerated" policies designed to protect racial minorities, women and LGBT people, among other vulnerable groups.

"The policies pursued by the Trump administration and congressional Republicans today could not stand in starker contrast to the values Paul championed," Franken said. "The values propelling the Republican agenda today are about consolidating political and economic power in the hands of corporations and the very wealthy."

As Franken spoke, several Democratic colleagues sat listening. For most of the speech, there was only one Republican — Sen. Lamar Alexander (Tenn.) — in attendance.

Franken thanked Alexander for seeking consensus and a shared understanding of the facts as chairman of the Senate Health, Education, Labor and Pensions Committee, of which Franken is a member.

"Thank you, Mr. Chairman, for when we've done that," he said.

Paul Kane and Karen Tumulty contributed to this report.

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