Separating Chicago from Illinois would be a good thing, provided you can get it passed. Section three requires the consent of the state legislatures, which would be hard to do considering the situation. They might be bribed by being told that they no longer have to deal with the country folk, but I'm sure they'd realize that they need the rest of the state to help fund stuff.
The separation would free the south from the Chicago machine, but would also change the national scene. Here's how it stands now:
Illinois: 2(maybe one)liberal senators, x many reps.
Afterwards, it would look like this:
Chicagoland: 2 liberal senators, y many reps
Illinois: 2 conservative senators(rural areas), z many reps
conservatives would gain two senators, and the liberals none, since because Chicago controls with population, they can overwhelm the southern areas. Once free, the southern areas would elect conservative senators. Reps, which are divided by population, would stay the same.