Democrats scrambled to contain the fallout on Thursday after sexual assault allegations against Sen. Al FrankenAlan (Al) Stuart FrankenFormer campaign aide to New Jersey governor says she was sexually assaulted by his ex-staffer Prosecutor drops some charges against Harvey Weinstein Poll: Dems maintain double-digit leads in Minnesota Senate races MORE (D-Minn.) shook the Capitol.

Senators quickly went into damage control mode after a reporter accused Franken of kissing and groping her without her consent during a USO tour in 2006. She released a photo of the then-comedian’s hands on her breasts while she was apparently asleep.

The allegations turned the tables in the Senate, where Republicans had been facing a daily barrage of questions about Roy Moore, the GOP Senate candidate in Alabama who is facing multiple allegations of sexual misconduct involving teenage girls.

Several Democratic senators distanced themselves from Franken, who had been considered a potential dark horse for the party’s presidential nomination in 2020.

“Sexual harassment and groping are never OK and never funny. … Senator Franken has begun addressing these issues by calling for an ethics investigation and saying he’s going to cooperate,” Sen. Richard Blumenthal (D-Conn.) said while declining to comment further because of the ethics probe.

Senate Minority Whip Dick DurbinRichard (Dick) Joseph DurbinDurbin opposes Saudi arms sale over missing journalist Noisy democracy, or rude people behaving like children? Kavanaugh tensions linger after bitter fight MORE (D-Ill.) said Franken’s behavior was “wrong,” while Sen. Tim KaineTimothy (Tim) Michael KaineElection Countdown: O'Rourke brings in massive M haul | Deal on judges lets senators return to the trail | Hurricane puts Florida candidates in the spotlight | Adelson spending big to save GOP in midterms Senators warn Trump that Saudi relationship is on the line Virginia police release surveillance video from Jewish center vandalized with swastikas MORE (D-Va.) called it “unacceptable.”

“What I saw was horrible. ... We got to make it clear that this is not humor. This is about power issues, gender issues,” Sen. Ben CardinBenjamin (Ben) Louis CardinBipartisan bill would block foreign adversaries from owning US election vendors Missing journalist strains US-Saudi relationship Democrats seek to turn Kavanaugh anger into votes MORE (D-Md.) said.

Leeann Tweeden, a radio anchor for Los Angeles’s KABC, wrote on Thursday that Franken crafted a skit involving Tweeden during the trip that included a kissing scene. She said Franken pressured her into practicing the routine and then aggressively kissed her despite her objections.

“I felt disgusted and violated,” she wrote. “I tried to let it go, but I was angry.”

Franken is the latest high-profile figure to face harassment allegations, with current and former female staffers increasingly emboldened to go public with the treatment they’ve received on Capitol Hill.

Four in 10 female staffers who responded to a Roll Call survey earlier this year said they believed Capitol Hill had a sexual harassment problem, while 1 in 6 said they had experienced it personally.

And the Senate, in response to pressure from both parties, passed a resolution late last week that made its anti-sexual harassment training mandatory for senators and staff.

The allegations against Franken initially appeared to catch Democratic senators flat-footed, with several declining to weigh in or noting they had just read stories about the incident as they made their way toward the Senate chamber.

Sen. Tom CarperThomas (Tom) Richard CarperTrump poised to sign bipartisan water infrastructure bill Overnight Health Care — Presented by the Coalition for Affordable Prescription Drugs — Senators face Wednesday vote on Trump health plans rule | Trump officials plan downtime for ObamaCare website | Lawmakers push for action on reducing maternal deaths Bipartisan group of senators ask Trump to increase focus on maternal deaths MORE (D-Del.), who later released a statement condemning Franken’s behavior, noted that he couldn’t talk because he needed to vote and “I don’t like to miss votes.” 

Democratic Sens. Jeanne ShaheenCynthia (Jeanne) Jeanne ShaheenBrunson release spotlights the rot in Turkish politics and judiciary Overnight Defense — Presented by The Embassy of the United Arab Emirates — Missing journalist strains US-Saudi ties | Senators push Trump to open investigation | Trump speaks with Saudi officials | New questions over support for Saudi coalition in Yemen Senators demand answers on Trump administration backing of Saudi coalition in Yemen MORE (N.H.), Brian SchatzBrian Emanuel SchatzGOP shrugs off dire study warning of global warming Dems to force health care vote weeks before Nov. midterms This week: Rosenstein set to meet with House GOP MORE (Hawaii) and Chrisotpher Coons (Del.) said they couldn't comment because they are members of the Ethics Committee. 

Sen. Elizabeth WarrenElizabeth Ann WarrenBiden leads crowded field of Dems in potential 2020 matchup: poll Trump attacks Democrat in Ohio governor's race Warren responds to 'arrogant woman' insult: 'Was I tough on John Kelly? ... You bet I was' MORE (D-Mass.), who frequently ignores reporters around Capitol Hill, avoided questions, while Sen. Maria CantwellMaria Elaine CantwellHillicon Valley: Facebook deletes accounts for political 'spam' | Leaked research shows Google's struggles with online free speech | Trump's praise for North Korea complicates cyber deterrence | Senators want Google memo on privacy bug Congress moves to ensure the greater availability of explosives detecting dogs in the US Overnight Energy — Presented by Southern Utah Wilderness Alliance — Trump ends law enforcement program at wildlife refuges | Pruitt canceled trips he already had tickets for | Senate panel approves new parks fund MORE (D-Wash.) remained silent as reporters asked her about Franken as well as drilling in the arctic. 

Sen. Joe ManchinJoseph (Joe) ManchinGillibrand backs Manchin, Bredesen despite their support of Kavanaugh Senate heads home to campaign after deal on Trump nominees Overnight Energy: Climate skeptic confirmed as DOJ environmental lawyer | EPA to phase out air pollution panel | Ad campaign targets mercury rule proposal MORE (D-W.Va.) appeared flabbergasted as he spoke to a swarm of reporters, repeatedly saying that he wanted to speak with Franken.

“I just heard. I just heard, and … I would like to hear from Al,” he said. “I just want to hear from Al. I just want to hear Al’s explanation.”

Franken kept a low profile throughout the day, skipping the Senate’s four votes and a closed-door Democratic caucus lunch.

A spokesman for Franken didn’t respond to a request for comment about his schedule, but sources told CNN that the senator apologized to his staff on Thursday.

The senator initially released a brief statement saying that he didn’t "remember the rehearsal for the skit in the same way, but I send my sincerest apologies to Leeann. ... As to the photo, it was clearly intended to be funny but wasn’t. I shouldn’t have done it.”

But that appeared to frustrate some of his colleagues, who were quick to say they believed Franken’s accuser.

“They are deeply concerning, and I expect to hear more from Sen. Franken,” Gillibrand told reporters during her press conference on military sexual assault.

She added separately that she did not believe Franken’s initial apology was sufficient.

Sen. Tammy DuckworthLadda (Tammy) Tammy DuckworthHillicon Valley: Facebook deletes accounts for political 'spam' | Leaked research shows Google's struggles with online free speech | Trump's praise for North Korea complicates cyber deterrence | Senators want Google memo on privacy bug Senate Dem: Trump's 'fake, hyperbolic rantings' an insult to real Medal of Honor recipients Meteorologist wears her toddler to work in support of working mothers MORE (D-Ill.), asked if she thought Franken’s accuser was credible, added, “I tend to believe her.”

“I think that women should be able to feel safe and free in their workplace, and if that there are such allegations they should come forward,” she added, asked if she was worried about additional allegations against Franken.

The Minnesota senator released a longer apology on Thursday afternoon and said he would cooperate with an ethics investigation.

“I respect women. I don't respect men who don't. And the fact that my own actions have given people a good reason to doubt that makes me feel ashamed,” Franken said in his second statement.

But Democrats were quick to get out ahead of Franken, coalescing behind an ethics investigation after Senate Majority Leader Mitch McConnellAddison (Mitch) Mitchell McConnellGOP Senate candidate: Kavanaugh 'debacle' 'hugely motivating' to Missouri voters Trump praises McConnell: He ‘stared down the angry left-wing mob’ to get Kavanaugh confirmed Murkowski not worried about a Palin challenge MORE (R-Ky.) publicly urged the committee to review the matter.

“I hope and expect that the Ethics Committee will fully investigate this troubling incident, as they should with any credible allegation of sexual harassment,” Senate Minority Leader Charles SchumerCharles (Chuck) Ellis SchumerFive takeaways from the final Tennessee Senate debate Schumer rips Trump 'Medicare for all' op-ed as 'smears and sabotage' GOP senator suspects Schumer of being behind release of Ford letter MORE (D-N.Y.) said in a tweet.

“Sexual harassment is never acceptable and must not be tolerated,” he added.

But Schumer, like most Democrats on Thursday, did not respond to a question about whether Franken should resign.

“I feel very strongly that Roy Moore should not be a senator, and I feel strongly that if he is elected that the Senate should have its own response to it. I expect to hear more from Sen. Franken on this issue,” Gillibrand said when asked if Franken should resign from the Senate like Moore should withdraw from his race.

Durbin, asked if Franken should resign, said, “No, no, no, no.”

“I think you go through the ordinary due process. And have this thing judged on its merits,” he said.

Asked if an investigation could lead to the committee recommending that the Senate expel Franken, Durbin added, “It could lead to any number of things. It’s not fair to prejudge it or judge what the committee will do.”

Franken isn’t on the ballot in 2018, but the fallout over his sexual assault allegations quickly spilled over into the midterm battle for the Senate, where Democrats face a challenging map. 

Republicans and allied outside groups quickly demanded that Democrats, in particular senators running in red states carried by President Trump, give back any campaign donations from Franken or his PAC.

Claire McCaskillClaire Conner McCaskillGOP Senate candidate: Kavanaugh 'debacle' 'hugely motivating' to Missouri voters Democrats hold fading odds of winning Senate this November Cornyn: 'All the money in the world' won't help O'Rourke win Texas MORE must denounce her Democrat colleague and return campaign donations she has received from him. … If McCaskill won’t immediately denounce Franken and return his donations, it will be clear she puts partisan politics over basic decency,” said Bob Salera, a spokesman for the National Republican Senatorial Committee (NRSC).

The NRSC released almost identical statements targeting other Democrats up for reelection, including Manchin and Sens. Jon TesterJonathan (Jon) TesterTrump adds campaign stops for Senate candidates in Montana, Arizona, Nevada Democrats hold fading odds of winning Senate this November Senate heads home to campaign after deal on Trump nominees MORE (Mont.), Bill NelsonClarence (Bill) William NelsonDisasters become big chunk of U.S. deficit Electoral battle for Hispanics intensifies in Florida Democrats hold fading odds of winning Senate this November MORE (Fla.) and Heidi HeitkampMary (Heidi) Kathryn HeitkampDemocrats hold fading odds of winning Senate this November Florida politics play into disaster relief debate Cornyn: 'All the money in the world' won't help O'Rourke win Texas MORE (N.D.).

Tester, asked if the NRSC was going too far, said, “I’ve been focused on the [Veterans Affairs] bill on choice. I haven’t been focused on this.”

“Have they asked the people who contributed to Roy Moore to ask for their money back?” Tester asked, as he headed into the Democratic caucus lunch.

But by late Thursday afternoon, Democrats were rushing to donate Franken’s campaign cash.

Tester said he would donate $25,000 in donations “to support the important work” of the Montana Coalition Against Domestic and Sexual Violence.

In addition to Tester, Democratic Sens. Sherrod BrownSherrod Campbell BrownLawmakers, Wall Street shrug off Trump's escalating Fed attacks The Hill's Morning Report — Presented by PhRMA — Dem victories in `18 will not calm party turbulence Election Countdown: Minnesota Dems worry Ellison allegations could cost them key race | Dems struggle to mobilize Latino voters | Takeaways from Tennessee Senate debate | Poll puts Cruz up 9 in Texas MORE (Ohio), Tammy BaldwinTammy Suzanne BaldwinHillicon Valley: Facebook deletes accounts for political 'spam' | Leaked research shows Google's struggles with online free speech | Trump's praise for North Korea complicates cyber deterrence | Senators want Google memo on privacy bug Poll: Baldwin leads GOP challenger by double digits in Wisconsin The Hill's Morning Report — Presented by PhRMA — Trump, Pence fan out to protect the Rust Belt MORE (Wis.), Claire McCaskill (Mo.), Joe DonnellyJoseph (Joe) Simon DonnellyThe Hill's 12:30 Report — Presented by Citi — Big haul for O'Rourke | Senators press Trump to get tougher on Saudis | Kavanaugh tensions linger The Hill's Morning Report — Presented by PhRMA — Dem victories in `18 will not calm party turbulence Senate heads home to campaign after deal on Trump nominees MORE (Ind.), Bob CaseyRobert (Bob) Patrick CaseyDem senators urge Pompeo to reverse visa policy on diplomats' same-sex partners The Hill's Morning Report — Presented by PhRMA — Dem path to a Senate majority narrows Trump rails against Dems at Pennsylvania rally as Hurricane Michael batters Florida MORE (Pa.), Gillibrand, Heitkamp, Manchin and Nelson each said they were donating their contributions from Franken.

“The allegations against Senator Franken are serious, hurtful and should be investigated. It was the correct decision for Senator Franken to ask for an Ethics Committee investigation,” Manchin said in a statement. “I am also returning his donations.”

Nelson, whom Franken was supposed to headline a fundraiser for this weekend, added that, "as for the events this weekend, Sen. Franken is no longer available." 

Alexander Bolton and Rebecca Kheel contributed