WASHINGTON (CBSNewYork/CBSNews/AP) — Sen. Al Franken‘s support among his fellow Democrats appeared to collapse Wednesday as a group of female Democratic senators called upon him to resign amid sexual misconduct allegations.

His office said he will make an announcement Thursday, but did not specify the subject.

Sens. Kirsten Gillibrand, D-N.Y., Patty Murray, D-Wash., Claire McCaskill, D-Mo., Mazie Hirono, D-Hawaii, Kamala Harris, D-Calif., Tammy Baldwin, D-Wis., Debbie Stabenow, D-Mich., and Maggie Hassan, D-N.H., called on Franken to step down.

Some Democratic men joined them, including Senate Minority Leader Charles Schumer, D-N.Y.

Talk radio news anchor Leeann Tweeden accused Franken of forcibly kissing and groping her during a USO tour in 2006. Three other women have also accused Franken of groping them.

Franken has apologized for his behavior but he has disputed some of the allegations.

In Facebook posts and Tweets, the women said the two-term senator should step aside after a fresh allegation that he forcibly tried to kiss a woman in 2006.

Sen. Kirsten Gillibrand wrote on Facebook that while 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.”

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

“Senator Franken should resign,” Schumer said Wednesday afternoon. “I consider Senator Franken a dear friend and greatly respect his accomplishments, but he has a higher obligation to his constituents and the Senate, and he should step down immediately.”

Democratic National Committee chairman Tom Perez also called on the senator to step aside.

Franken’s Minnesota colleague, Sen. Amy Klobuchar, did not demand his resignation, but tweeted Wednesday that she had spoken with him about his announcement and is “confident he will make the right decision.”

Sexual harassment is unacceptable. This morning I spoke with Senator Franken and, as you know, he will be making an announcement about his future tomorrow morning. I am confident he will make the right decision. — Amy Klobuchar (@amyklobuchar) December 6, 2017

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