Advertisers can buy spots for a single day or for a few hours, rather than weeks at a time as on normal billboards.

A younger audience has implications for the type of advertisers buying spots on the show.

Instead, for less money, some sponsors buy 30-second spots in a handful of major cities.

Unlike in print or television, search engine advertisers buy spots without knowing how many times their advertisements may be seen.

They are buying spots on cable for their candidates and exploring other ways of using the nation's 5,000 cable television systems.

Other advertisers, including several movie studios, have bought spots but do not want to identify themselves until closer to game time.

Broadcast networks have generally cited race sponsors sparingly if they didn't buy spots.

If we buy spots, we'd look for the same thing.

And those sponsorship dollars wouldn't be contributed at this level if they could not buy spots on national television with them.

And advertising agencies that buy spots for big clients demand a ratings guide to justify their decisions.