Democratic Sen. Al Franken on Thursday said he will resign from the Senate in the coming weeks in the face of mounting accusations of sexual misconduct before and during his time in office. His stunning exit will scramble Minnesota's political climate heading into the 2018 midterm election.

Franken had spent the past three weeks pleading for forgiveness in response to the accusations over his past actions. He'd hoped to make his case to the Senate Ethics Committee that his behavior shouldn't require him to give up the seat, though at least eight women shared stories of him touching them without consent during photo-opportunities, on a celebrity tour to military installations abroad or at political events.

The common pattern they described included allegations that Franken groped their buttocks or breasts or tried to kiss them.

Standing on the Senate floor Thursday, he said he could no longer be an effective senator for Minnesota. But he insisted that some of the allegations against him were "simply not true ... others, I remember very differently."

He said he was proud of being a champion of women while in the Senate.

"I know in my heart that nothing I've done as a senator, nothing, has brought dishonor on this institution," he told assembled senators. "I know who I really am."

Sen. Al Franken, D-Minn., and his wife, Franni Bryson, arrive at the U.S. Capitol Thursday. Chip Somodevilla | Getty Images

He also took a shot at President Trump and Roy Moore, the Republican Senate candidate from Alabama.

Franken indicated he thought it was ironic that while he's leaving, "a man who has bragged on tape about his history of sexual assault sits in the Oval Office and a man who has repeatedly preyed on young girls campaigns for the Senate with the full support of his party."

Franken's family members sat in the Senate gallery, some of them crying. Staff lined up in the back of the chamber, stone faced. And around 18 Democratic senators quietly listened to his speech on the floor. No Republicans were present except the chamber's presiding officer, Alaska Sen. Dan Sullivan.

The senator was halfway through a second term. His seat will be filled by Democratic Gov. Mark Dayton. That person will serve only through the 2018 election before voters get to select a senator.

It also means that both of Minnesota's U.S. Senate seats will be on next year's ballot, a first since 1978. With a heated governor's campaign and a handful of big congressional races on the horizon, the open seat will only invite more national attention and outside money into the state.

For Franken, the comedian-turned-politician, it marks a stunning fall from power.

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Elected in 2008 by a bare 312 votes — an outcome that required a meticulous recount and court case to reach — Franken brought a progressive voice and staunchly liberal voting record to the Senate. When he stood for a second term in 2014, he won with ease.

During Republican President Trump's first year, Franken emerged as a fierce foe of the administration. He aggressively challenged the administration's policies and nominees.

His questioning of now-Attorney General Jeff Sessions under oath exposed inconsistencies that some credit with causing Sessions to recuse himself from the investigation into Russian election interference.

Those moves, coupled with Franken's celebrity and immense fundraising ability, landed him on lists of potential 2020 Democratic presidential candidates.

But Franken's stature sunk like an anchor on Nov. 16. That's when Los Angeles radio show host and former model Leeann Tweeden went public with allegations of sexual harassment.

She said Franken kissed her in an unwelcome way during rehearsal for a skit during the USO Tour both were on in Afghanistan in 2006, before Franken was a senator. And she shared a photo of Franken with a naughty grin as his hands reached toward her chest as she slept on a military flight.

Franken apologized to Tweeden for the photo while insisting he didn't share her recollection of the kiss. To date, he hasn't provided his own account of that encounter.

But before long, other women had emerged with Franken stories of their own.

They included a woman who said that Franken put his hand on her buttocks during a picture pose at the Minnesota State Fair in 2010.

An Army veteran also alleged Franken cupped her breast during a photo opportunity on a USO tour in 2003. Two additional women also made anonymous claims against Franken in a Huffington Post article.

University of Minnesota Duluth students watch U.S. Sen. Al Franken's resignation speech at the Kirby Student Center. Derek Montgomery for MPR News

Franken didn't dispute the bulk of the allegations, issuing multiple statements and saying in interviews that he didn't recall them specifically and never intentionally touched women in a sexual way. But he also apologized profusely and said he was committed to regaining the trust of women and the public at large.

In an interview with MPR News' Cathy Wurzer on Nov. 26, Franken said he was taking responsibility for his behavior.

"I have been reflecting on this," he said. "I want to be a better man."

"I'm someone who, you know, hugs people," Franken said. "I've learned from these stories that in some of these encounters I have crossed the line for some women."

He returned to the Senate a day later and said he wanted to get back work, fighting the Republican tax plan and a proposal to loosen internet speed regulations. But days later, more allegations surfaced.

On Wednesday, a seventh woman made an allegation, though anonymously, telling the online publication Politico that Franken tried to forcibly kiss her after a taping of his radio show in 2006.

Franken categorically denied the claim. But that last allegation was enough for most of Franken's fellow Senate Democrats to call for him to step down immediately rather than wait for the ethics committee to do its work.

Sen. Al Franken, D-Minn., arrives with his wife on Capitol Hill in Washington, Thursday. Andrew Harnik | Associated Press

The public emergence of another woman late Wednesday saying Franken had groped her accelerated the pressure.

This wasn't the first time Franken's posture toward women had caused him political problems. Running for the seat a decade ago, Franken had to explain writings that included rape jokes and other demeaning comments.

He said at the time that those were pure satire, which was his trade as a "Saturday Night Live" cast member and an author.

His electoral success had put some of those concerns to rest, and Franken went to work on legislation enhancing women's rights. He pushed measures to aid victims of sexual harassment and assault.

Those actions left his supporters in a difficult spot when the allegations came to light. Some backers were willing to cut him slack and they fought comparisons of Franken to other high-profile figures accused of sexual harassment or worse. Dozens of women who worked for Franken or shared a political party with him vouched for him and said he shouldn't be forced out.

Dayton on Thursday said he had not yet decided on who he'll tap to fill Franken's seat. The governor, though, is almost certain to appoint a Democrat.

Franken's exit will have big implications for 2018.

Senate Republicans had been veering mostly clear of Minnesota given Democratic Sen. Amy Klobuchar's popularity and better opportunities elsewhere.

Alan Carpenter, right, and other pedestrians, who declined to provide their names, stop in the Minneapolis skyway to watch Sen. Al Franken announce his resignation on CNN. Evan Frost | MPR News

But an open seat could be a tantalizing new target as the GOP looks to protect, and possibly expand, a two-seat majority.

Loads of money could flow into the state that otherwise wouldn't, giving down-ballot Republicans a potential turnout lift. National Democrats would have to spend money they otherwise wouldn't to defend the seat.

The winner of the 2018 election would serve the remainder of Franken's term, putting the seat back on the ballot in 2020.

Franken lingered on the Senate floor after his resignation speech Thursday, hugging colleagues and staff after yielding the floor.

He later walked out of the building through a ground floor corridor, hand-in-hand with his wife Franni and surrounded by police and media.

Asked if he had any comment for Minnesotans, he said only, "I'm coming home." He and his wife made their way to a waiting SUV and drove away.

MPR News reporter Tim Nelson contributed to this report from Washington, D.C., as did the Associated Press.

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