Transcript for At least 38 senators call on Al Franken to resign
Back here at home, and next to Al Franken tonight. The democratic senator has now revealed he will make an announcement tomorrow. Of course, the question, will he resign amid growing pressure from several prominent women in the senate who began an avalanche of senators today who now say he must go. ABC's Mary Bruce, back on the hill tonight. Reporter: The cascade of calls for Al Franken to go started this morning with a handful of women senators. Enough is enough. Reporter: It appeared to be a coordinated strike, one after another, they flooded social media. By the end of the day, at least 28 senators were calling on Franken to resign. You're saying he should resign? And I get no pride or pleasure in saying that. Thank you. Reporter: Just days ago, most Democrats were holding their fire. This was senator Patty Murray of Washington. The senate ethics committee should do an investigation and that's where I believe it should go. Reporter: But today, a starkly different tone. Murray tweeting, "I'm shocked and appalled by senator 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. What was the tipping point here? Why today? The numerosity and the type of complaints and accusations. Reporter: Just hours earlier, another woman had come forward, saying Franken forcibly kissed her. The senator denies that allegation. Tonight, eight women in total have accused Franken of sexual misconduct. The first, radio host Leeann tweeden, who released this photo. I think today's revelations just further add to a fact pattern here that's just unacceptable. Reporter: Franken has apologized and promised to make amends. I know there are no magic words that I can say to regain your trust. Reporter: But tonight, the trust of his colleagues now appears lost for good. All right, Mary Bruce live back on the hill tonight. And Mary, you've been working your sources what do we know about this promised announcement from senator Franken? Reporter: Well, David, Franken's office says no final decision has been made, but multiple democratic sources tell us he is, in fact, expected to announce his resignation tomorrow. David? All right, Mary Bruce, you'll be on the hill again tonight. Thank you.
This transcript has been automatically generated and may not be 100% accurate.