I think if Obama can keep Indiana within 2-3 and McCain under 50, his much, much superior ground-game in the state should make the difference.
I have heard this repeatedly from Obama supporters and it totally misrepresents what a 'groundgame' is. A groundgame does not magically manifest on election day. Instead it is the phone calls, door knocking, and talking within the community has been taken place over months. Yes, the Obama campaign is doing more of that, and yes, it will continue to do more of that until election day. But results of the past three months of 'groundgame' are reflected in the polls already. The only place were groundgame really matters the day of election is the caucus states. The .001% of people that are driven to the polls by members of Obama's 'groundgame' are not going to swing this election.