Sen. Al Franken's political career is in peril after dozens of his Democratic Senate colleagues called on him to resign his seat amid a slew of accusations of sexual harassment and groping.

The Minnesota lawmaker's office says he is planning to respond on Thursday.

Democrats were already using their unified condemnation as a contrast with the Republican Party's support for President Trump, who's been accused by several women of similar behavior, and Alabama Senate candidate Roy Moore, an accused child molester who this week received an endorsement from Trump and cash infusion from the Republican National Committee.

Hours after a report by Politico about a new accuser, senators including Claire McCaskill of Missouri, Kirsten Gillibrand of New York, Kamala Harris of California and Sherrod Brown of Ohio, said the Minnesota lawmaker must go.

Top Democrat Chuck Schumer joined in the call for resignation Wednesday night.

Politico cited an unnamed Democratic congressional aide who said Franken cornered her in a studio in 2006 and forcibly tried to kiss her. Franken was elected in 2008 and had a long career as a comedian before that.

“I’m shocked and appalled by Sen. Franken’s behavior. It’s clear to me that this has been a deeply harmful, persistent problem and a clear pattern over a long period of time,” Murray said in a statement. “It’s time for him to step aside,” she said.

“While Senator Franken is entitled to have the Ethics Committee conclude its review, I believe it would be better for our country if he sent a clear message that any kind of mistreatment of women in our society isn’t acceptable by stepping aside to let someone else serve," Gillibrand posted on Facebook.

Senate Majority Leader Mitch McConnell also weighed in: “The near daily barrage of allegations of sexual misconduct against Senator Franken are extremely concerning to all of us in the Senate. ... I do not believe he can effectively serve the people of Minnesota in the U.S. Senate any longer.”

McConnell, who initially suggested the Senate would expel Moore if he were elected next week, has since said Moore's future is "up to the people of Alabama."

According to the Politico report, Franken approached the unnamed aide after her boss had left the broadcast studio. She said she was gathering her belongings when she turned around to find Franken in her face, attempting to kiss her. The two did not know each other.

"The number of accusations hit critical mass," said Jennifer Duffy, a Senate analyst at the nonpartisan Cook Political Report. If Franken resigns, the state's Democratic governor, Mark Dayton, would appoint a successor to serve until the next election in 2020 or until a special election can be held.

Franken, a former comedian and Saturday Night Live cast member, was the first sitting lawmaker in Washington to be publicly accused. A Senate ethics panel opened a preliminary inquiry after at least six women accused Franken of groping and other unwelcome conduct.

Rep. John Conyers, D-Mich., the longest-serving member of the House, announced his resignation Tuesday in the wake of multiple sexual harassment claims against him.

Wednesday's crashing wave of condemnation by Democrats that came in rapid succession after the latest accusation -- allows the Democratic Party to distinguish itself from Republicans at a time when sexual harassment is becoming a major national flash point. Democrats in the House and Senate have now called for the resignation of the three party members accused of sexual harassment or misconduct, including Rep. Ruben Kihuen of Nevada.

Trump and the RNC are trying to help Moore across the finish line, even as nine different women -- many of them identified -- have provided accounts about their experiences with Moore as teenagers, including one who said he molested her when she was 14. House leaders have also been quiet about Rep. Blake Farenthold, R-Texas, who settled a sexual harassment suit in 2015 using taxpayer money and whose accuser says she was subsequently unable to find employment in Washington.

"Where are the Republican voices? Where is their outrage?" Sen. Mazie Hirono, D-Hawaii, said, calling the stance on Moore in particular a "totally inappropriate position."

McConnell's muted response to Moore late in the Senate race is likely designed to counter his unpopularity in the state as former Trump strategist Stephen Bannon is making him a political target. It's unclear if McConnell's attempts to chastise Moore could backfire with many Alabama voters who believe Moore is getting railroaded by the Democratic Party and the media.

The Democratic Party is also trying to inoculate itself against charges of hypocrisy, said Duffy. “It’s hard to accuse Republicans of waging war on women and to be the party that says we are fully supportive of women’s rights and things like equal pay and then not react” to harassment charges, she said.

Franken has apologized and said he welcomes an ethics investigation even as his spokesman released a statement saying that Franken “has never intentionally engaged in this kind of conduct.”

Stephanie Kemplin of Ohio, who says Franken cupped her breast as the two posed for a photo in 2003 while she was stationed with the Army in Kuwait, is the most recent named accuser to come forward. Others include radio and sports broadcaster Leeann Tweeden, who says Franken stuck his tongue down her throat and later pretended to grope her in a picture while she was sleeping. The alleged incidents took place during a 2006 USO tour in the Middle East to entertain U.S. troops, before Franken was elected to the Senate.

Franken has pledged to cooperate with a Senate Ethics Committee investigation and said he “is open” to making the results public.