Last fall Brooks ran for mayor and lost but still ended up with 48% of the vote.
"What I re-discovered is that as you get understanding and communicate there's a lot more common ground than uncommon ground and I really enjoy finding that common ground with all peoples."
Brooks has worked as a family advocate for the King Center in Rock Island where he helps people find jobs, housing, and other resources. He also helped convince the city council to create the Rock Island Police Community Relations Commission.
Brooks is named for the famous civil rights lawyer and supreme court justice Thurgood Marshall.
"I do think it inspired me in some ways. To have interest in... I studied history and political science in school and so I do think my name has something to do with my interest in history and what we're doing here now."
Last year he was named Rock Island Citizen of the Year.
The other two Democrats who are also running for the Illinois House are Jeff Deppe and Gregg Johnson. The primary will be held in June.