STORY UPDATE: Sen. Al Franken resigning amid sex misconduct scandal

MINNEAPOLIS - Embattled Senator Al Franken will make an announcement from the Senate floor Thursday morning, one that could signal a significant shift in Minnesota's political landscape.

A post on Franken's Twitter account Thursday morning said he will make that announcement around 10:45 a.m. Central Standard Time.

The pressure on Franken has been growing since two more women stepped up Wednesday to accuse him of inappropriate sexual conduct. Those accusations triggered an avalanche of calls from dozens of his senate colleagues to resign.

While Thursday morning's Twitter post gives no mention as to what Franken's announcement will include, long-time political science professor Steven Smith believes it will be his resignation.

"That gives the governor 24 hours to scramble and make some new plans," Smith said.Under Minnesota law, Governor Mark Dayton will first name an interim replacement for Franken.Then, at the August 14, 2018 primaries, voters will elect a candidate from each party.At the General Election on November 6, 2018, voters will select the new senator to finish the last two years of Franken's term.Finally, in November 2020, there will be another election for a new six-year term.Smith says Dayton's immediate appointment is very important."Because that person would have a leg up, be serving in the Senate. And gain a lot of free publicity," Smith said.RELATED: Democratic senators call on Franken to resign, 'announcement' Thurs."I think probably, given the current atmosphere, he'd likely look to a woman," said former St. Paul Pioneer Press political reporter Rachel Stassen-Berger.Stassen-Berger suspects Dayton already has informally been thinking about potential replacements in the event Franken ends up resigning."You'd have to look at someone like Lori Swanson, the Attorney General, perhaps Lieutenant governor Tina Smith, Both Democrats, both women," Stassen-Berger said.But Dayton also will decide whether to appoint a placeholder or someone he'll endorse through the primary.Sen. Amy Klobuchar is up for re-election next year. So if Franken resigns, both seats will be on the ballot at the same time.That's rare, but it happened in Minnesota in 1978 after Hubert Humphrey died. And that year, Republicans captured both seats.