The instructions for Illinois Schedule CR specifically state that "gambling, sports wagering, and lottery winnings" from other states should be entered on Line 15, Column B.
il-1040-schedule-cr-instr.pdf (illinois.gov)
In 2015 the U.S. Supreme Court ruled that states may not tax income that is already subject to taxation by another state. It held that states must provide credits to individuals or business to avoid double taxation of the same income.
https://www.scotusblog.com/case-files/cases/comptroller-v-wynne/
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
