Pennsylvania will be closely tied to Ohio, as will Michigan. The better Bush does in Ohio, the better he will do in the other two. I think Ohio will be the easiest to win, followed by Penn., followed by Michigan. Bush will probably do four points worse in Pennsylvania than he does in Ohio, and eight points worse in Michigan. So...
If Bush wins by five points in Ohio,
he takes Penn. by one point,
and loses Michigan by four.
If Bush wins Ohio by nine points,
he takes Penn. by five,
and takes Michigan by one.
Or some correlation very much like that.
You're extrapolating from 2000 too much - I suspect Bush will do about the same in Ohio and Pennsylvania this time. Maybe a point or two better in OH. My point is that while OH is traditionally a GOP state it has stayed static while PA has moved right. They're probably at a similar point right now.
