The Obama campaign is really big on early voting (or at least they were during the Texas primary). Then again, Obama won among early voters in Texas, and a lot of good that did him in the end.
yeah, but Texas was demographically very difficult for him, and he came very close to winning. Without the early voting effort he would likely have lost by even more.
I think this is where the difference between the general election and primary elections comes into play. Early voting helps candidates bank their strong voters' votes. In a primary, where election day turnout is lighter, that helps. In a general election, it doesn't hurt, but it doesn't move the needle as much. Of course it's helpful if the McCain campaign doesn't have a least a passable early voting campaign to match it...