Next, go here:
http://www.homezonebc.com/fares/index.html
For example, there's a DEN-MKE fare of $183 valid 30-Jun thru Jul 9. It allows four transfers each way, so you might be able to do something like:
DEN-IAD-SFO-ORD-MKE
You get the idea. Find the fare, and then play with the route.