In what may be the single most expensive political ad ever, the Obama campaign will air a 30-minute ad next week that is reported to have cost $6 million, Newsweek reports.

“The Obama show, airing on the major broadcast networks (NBC, CBS and Fox are confirmed; ABC is still in talks) and three cable news networks, will be the last big set piece of the extraordinary 2008 presidential campaign. One senior source close to the campaign puts the price tag in the $6 million range—which would make it the most expensive single political ad ever.

“Broadcasts like the Oct. 29 infomercial were not uncommon in the 1960s. But the prohibitive cost has kept candidates from pursuing this path in recent years. Hillary Clinton bought a block of time on the Lifetime cable network during the primaries this year. But the tactic hasn’t been used on network television since Ross Perot aired a memorable mix of charts and folksy catchphrases back in 1992.”

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