Alachua is a university town. Leon is a university and government town. Ads won’t help there.
But most people in North Florida don’t live in Alachua and Leon Counties. They live in the Jacksonville area (1.5 million) and the NW Gulf Coast Pensacola-Fort Walton-Panama City area. Those two regions vote heavily GOP.
Volusia isn’t a part of North Florida.
Romney should run ads in Central Florida -which is up for grabs. He should also run ads in South Florida, which votes heavily Democrat - but I think he could peel off a great deal of the Jewish population by running footage of the Democrats booing Israel at the convention.
McCain took Duvall by a scant 1% in 2008. 192k to 197k, and the gimme dat welfare crowd has expanded mightily in North Florida in the last four years. If you don’t think R2 needs to fight for every vote your not accounting for the effect of the growth the entitlement crowd.