State Sen. Daniel Biss, whose name has been in the mix as a possible Democratic challenger to Gov. Bruce Rauner in his 2018 re-election campaign, announced he will make a major announcement Monday via Facebook Live.

It’s unknown whether Biss, who helped to raise $10 million to run anti-Rauner ads before the November election, will announce a run for governor. A spokeswoman declined to elaborate on the nature of his announcement.

Biss sent notice to the media that he will “speak to fellow Illinoisans” at 10 a.m. via Facebook Live “to address his plans to build a movement to take our state back from wealthy and insider interests.”

Biss, a resident of north suburban Evanston, currently represents the 9th District in the Illinois Senate and previously served one term in the Illinois House representing the 17th District.

Biss grew up in Bloomington, Indiana, and moved to Chicago after obtaining his bachelor’s degree at Harvard University and a Ph.D. in mathematics at the Massachusetts Institute of Technology, before joining the University of Chicago’s mathematics faculty at 25.

He has said that while teaching, his desire to confront Illinois’ most critical problems compelled him to get more involved in his community, first as an organizer, and later as an elected official. He and his wife, Karin, have two children.