Traffic to OHare on Sunday

Hi all! We’re heading to O’Hare on Sunday to fly out for vacation. Just got a message from the airline warning us to leave extra arrival time because of the marathon. Flight is at 3:45, planning to arrive at the airport at 1pm. We’re coming up I-57 from Champaign, which is normally about a 2 hour drive.

Any insights into how bad the traffic will be?