Every year, dozens of marketers spend dearly during the Super Bowl to try to dazzle viewers, win the various ad polls and claim creative bragging rights for their industry.

The ad battle creating the most excitement this year is Coke vs. Pepsi, companies with a long and tortured marketing rivalry that haven't faced off in a Super Bowl brand war in about a decade.

It is a pivotal marketing moment for both companies — and not just because more than 90 million people will be watching. Coca-Cola, which struggled with its marketing message for years, has recently gotten its advertising mojo back. Last year, the Atlanta beverage company won two awards at the Cannes International Advertising Festival in France.

PepsiCo has long had a leg up on its archrival in the ad department, thanks to the use in its ads of celebrities and popular musicians, including Michael Jackson. But in recent years, as the company departed from that formula, its ads haven't lived up to its past successes.

During the Super Bowl, Coke will promote its slogan "The Coke Side of Life" with one spot that features a scene from the Macy's Thanksgiving Day Parade. The Underdog and Stewie balloons fight over a Coke balloon but are beat out by Charlie Brown, according to a person familiar with the spot. Another ad, filmed on Connecticut Avenue in Washington, features former Senate Majority Leader Bill Frist, a Republican, and political consultant James Carville, a Democrat, playing a game of "jinx" (when two people utter the same word simultaneously). They end up playing nice over a bottle of Coke. The spots were created by Wieden+Kennedy.

Pepsi's ad arsenal includes a return of the use of celebrity pitch people. In one, as a young woman sips a Pepsi through a straw, pop star Justin Timberlake is seen being sucked through life — bumping into objects such as a car door and a parking meter. Omnicom Group's BBDO crafted the ad.

While both companies had ads in last year's Super Bowl — Coca-Cola jumped back in after a nine-year hiatus — PepsiCo didn't run ads for its Pepsi brand, instead peddling its Sierra Mist soda.

Both cola makers are playing down the matchup this year. "We always hope to do better than the competition, but that is not what drives us," says Dave DeCecco, a spokesman for Pepsi. "We just want to connect with our consumers in the strongest possible way."

Katie Bayne, chief marketing officer of Coca-Cola North America, says, "Pepsi is a great competitor of ours, but honestly, as we look at the game, it doesn't have much to do with them. It has more to do with the growth behind Coca-Cola."

U.S. sales of both Coca-Cola and Pepsi-Cola are declining sharply. In the first nine months of 2007, sales of cases of Coca-Cola Classic declined 5.6 percent, while Pepsi-Cola's volume slid 8.3 percent, according to Beverage Digest, an industry publication. Both companies are suffering from the broader decline in soda sales as more people switch to water and juices.

While a few good ads aren't likely to change the numbers dramatically, a return to the cola wars of old could help provide a mini sales spark, some industry analysts believe. In the mid-1980s, during the famous taste-test commercials, the companies saw a surge in publicity and consumer interest.

"For many years, the cola wars helped grow both companies," says John Sicher, editor and publisher of Beverage Digest.

Coke-Pepsi isn't the only intraindustry ad battle Sunday. Consumer-products companies Procter & Gamble and Unilever will be going at it, as will General Motors and Toyota Motor and a long list of movie studios. There will be more than 10 movie spots this year — only a handful of movie trailers aired during last year's game.

One advertiser makes sure it doesn't have the competition to worry about come game day. For years, Anheuser-Busch has been buying such a large quantity of ads that it gets to be the exclusive alcohol advertiser during the game.