The problem we have here in Illinois is that Chicago is its own state aside from the rest of Illinois. Durbin knows and my guess is Obama does too from his state government experience. Simply put, neither one cares. They count on their votes from Chicago and they do Chicago's bidding regardless.
I would love to see durbin ousted. Maybe then Illinois can join ranks of states that have SANE representation!
We have the same problem in Maryland. Baltimore (and Prince Georges county) basically decides our statewide (and national) elections. I live in Baltimore though, so perhaps my letters might carry a bit more weight, but I doubt it.
It's all about rejecting anything conservative with these people, no matter where you come from in the state. I don't have any illusions to the contrary. I still think it's a good idea to write to my senators though. It's the same concept as the "Chinese water torture": A persistant drip drip of contrary opinion can be rather annoying, when done consistently over time. ;)