This proposed amendment to Article IX, Section 3 to the Illinois Constitution would repeal the requirement that the state personal income tax be a flat rate and instead allow the state to enact legislation for a graduated income tax.
Source for Popular Vote data: Illinois State Board of Elections. Official Canvass General Election November 3, 2020, Illinois State Board of Elections (https://quincy-network.s3.ca-central-1.amazonaws.com/wp-content/uploads/sites/12/2020/12/2020-Final-Vote-Totals-Book.pdf) (accessed 7 Dec 2020)