And more could emerge before the filing period closes early next week.
Those filing Monday include Democrats Marlon Kimpson, Emmanuel Ferguson, and Margaret Rush.
Ferguson is a prosecutor in the 9th Circuit Solicitor’s Office. He also has worked at Burke High School as a student-teacher, then taught social studies at the Military Magnet Academy in North Charleston.
Rush, a Charleston businesswoman, is a former minority outreach director for RoadWise, Charleston County’s road-building program.
Kimpson works as a plaintiff’s lawyer and is a former chairman of the State Election Commission and former vice chairman of the State Democratic Party.
They are expected to face other Democratic candidates, including Herbert S. Fielding, who said he plans to file this week. He is the son of Herbert U. Fielding, who held the Senate seat from 1984 to 1992. Former Charleston City Councilman Maurice Washington also is expected to file soon.
Real estate agent Billy Shuman has filed for the seat as a Republican.
Also, state Rep. Seth Whipper, D-North Charleston, has said he is considering a bid.
Ford resigned the seat last month as the Senate Ethics Committee determined that he broke several campaign finance laws.
The District 42 seat stretches from downtown Charleston through North Charleston to southern Dorchester County.