“You’d also have to take out several other counties in northern Illinois like Will, Lake, and Dekalb.”
Lake for sure. Will is getting more liberal, and Dekalb only trends liberal because of the university (there are not many people in Dekalb County who are not associated in some way with NIU).
Lake was Conservative until the housing bubble brought yuppie liberals north. Lake had lower taxes (gas was cheaper on the Lake side of Lake-Cook Rd) and better schools. Liberals moved in taxes went up and schools pushed a gay agenda, conservatives fled to Kenosha. It was amazing to watch, people moved to Deerfield for the quality of life and then voted in policies that they fled in Cook county?