269-269 tie. Assuming the GOP keeps the House, this is a Romney win.
Romney could also win Wisconsin (win outright) in this scenario, theoretically. That said, I doubt Romney wins WI without also winning OH.
I seriously doubt he wins Nevada while losing Ohio.
Anyway, he's likely toast without Ohio.
Nevada is a much better electorate for Romney than Ohio and I think Romney closes the gap by the election. This is a feat I can't see him replicating in a place like Ohio.
Furthermore, Obama is up by ~5 points in Nevada vs ~3 points in Ohio (per RCP averages). So it's not like it's a blowout in one state or the other, both are up for contention.
