Dom Caristi, a telecommunications professor, believes the game between Oakland and Tampa Bay could reach nearly half the nation. A 30-second commercial costs $2.1 million for Super Bowl XXXVII.

"Forty years ago most of the country may have watched Ed Sullivan on a Sunday night, but even the highest rated shows today don’t get a majority of the population watching," Caristi said. The Super Bowl is the one event still watched by the majority of Americans."

A recent study found nearly 100 percent of adults 18-49 watching the Super Bowl hang around for the commercials.

"The cost of an ad is still valuable because of the added buzz that a commercial receives when it premieres during the Super Bowl," Caristi said. "Newspapers, newscasts, magazine articles and radio talk shows discuss the advertising for weeks before and after the game."