I took a look at the 2000 presidential race, and a quick calculation showed that one could have added sufficent votes for Bush to have won every county in Illiniois except Cook county and if he keep the same precentage in Cook he would still have lost by half a million votes.
I agree with you that Keyes needs to pay A LOT of attention to downstate, but he can't wrtite off Cook county. As to getting down there on the first day, I doubt enough voters are paying attention yet to know who he is, let alone where he's going. It does take more than a day or two to set up the logistics of a barnstorming tour around the state, does it not?