Nate Cohn discourages putting too much faith in it:
[I]f the polls confirm that Obama only leads by 1 or 2 points in the Buckeye State, Obama fans shouldn't be overly confident. In recent years, state polling averages have occasionally differed from the results by modest margins. Following the first presidential debate four years ago, Kerry took a lead in the majority of polls in Ohio for two weeks. On Election Day 2004, Kerry trailed by only a fraction of a point in Florida but went onto lose by 5 points. Four years ago, the polls were off by a modest amount in states like Iowa, Colorado, and Nevada. And in 2010, Democratic Senate candidates outperformed the averages across the country. None of this is to say that Democrats shouldn't be pleased by a slight lead in Ohio, just that it's not wise to be too confident if your route to victory depends on a slight lead in one state.
The Dish 