Barack Obama's campaign announced late Thursday that it has purchased 30 minutes of prime-time TV on Oct. 29, less than a week before Election Day, for the Illinois senator to make his closing argument to voters. Deals have been struck with CBS and NBC, while the campaign is reportedly still in negotiations with Fox News and other networks.

Ross Perot was the last candidate to employ the half-hour campaign infomercial strategy in 1992, but Vanderbilt University political science professor John Geer said purchasing big chunks of air time close to the election used to be common; Ronald Reagan and Jimmy Carter both made similar buys.

"I think it's smart politics" for Obama, Geer said. He noted that the utility of additional 30-second TV spots diminishes at the level of saturation that Obama and John McCain have achieved this cycle, so doing something different could be a good use of funds. And "Obama has enough money to be able to do this," he added.

With the country in the grip of a worsening economic crisis, voters are looking for a steady leader to guide them through an uncertain time, Geer said. One of Obama's biggest challenges, the professor said, has been to make voters comfortable with him as a president. He has seemed "unflappable" during the recent economic upheaval and, "given his rhetorical skills," a long spot from Obama is likely to be well-done. It could turn out to be the "modern equivalent of the fireside chat," Geer contended.

Geer also predicted that McCain’s camp might try to "redistribute" its resources to try something similar, giving the Arizona senator an equal chance to speak directly to voters.