Illinois voters will get to decide the future of the state’s income tax. Democrats on Monday approved a measure to put a graduated income tax on the ballot next fall.

A report issued by the University of Illinois Institute of Government and Public Affairs indicates that Illinois could raise more tax revenue, with a serious change in residents’ economic behavior, if it used a graduated income tax structure similar to those in neighboring states.

The Illinois Senate is moving the state closer to a major overhaul of its tax system. Senate Democrats approved a constitutional amendment that would change Illinois’ flat income tax to one that’s graduated — where the wealthy pay more.

After years of campaigning, Democrats are moving ahead with a plan to change Illinois’ tax system. On Tuesday they formally introduced the language they want to change in the Illinois Constitution.

Illinois Governor J.B. Pritzker said Thursday he’s confident the legislature will approve a graduated income tax.