When the green flag drops Saturday night at Daytona International Speedway, NASCAR fans will be fixed on the track to see who wins a key summer race.

For Coca-Cola Co., the race is a chance to reach fans on a Fourth of July weekend when they're likely stocking coolers and refrigerators with lots of beverages.

Atlanta-based Coke is the title sponsor of the race, named the Coke Zero 400 Powered by Coca-Cola. It will run NASCAR-themed commercials featuring a pair of Coke brand managers known for going after Coke Zero for "taste infringement."

And if a Coke-sponsored driver wins this weekend's Sprint Cup race, everyone in the United States 13 years and older can get a free 20-ounce Coke Zero by visiting www.cokezero.com.

A Coke driver winning is "like the cherry on top of the sundae," said Bea Perez, senior vice president of integrated marketing for Coca-Cola North America. "That's the great ending to the day. But for us, we have to win before the fans even get into the racetrack and before that green flag drops. For us, it's about the full experience, not just about our drivers being in victory lane."

On this day of Coke-sponsored racing, though, archrival PepsiCo will not be left out. Coke might have the race and track, but Pepsi has the most marketable drivers, said Ralph Santana, vice president of sports, media and interactive marketing for Pepsi-Cola North America.

Dale Earnhardt Jr. drives a car sponsored by AMP Energy, a Pepsi-owned energy drink. Pepsi also is a long-term sponsor of Jeff Gordon.

"We're betting on the power behind the drivers and not necessarily the name of the race," Santana said. "It's the power of Dale and the power of Jeff. ... AMP Energy is not sold at the track, but I can guarantee you all of Dale's fans will have some AMP Energy in their coolers and in their RVs or wherever they're watching the race from."

In the rivalry between Coke and Pepsi, NASCAR has provided a venue ripe for competition. This weekend's race is a prime example.

The Daytona summer race had been titled the Pepsi 400 until Coke signed a deal last year to become the title sponsor starting in 2008.

Coke now has pouring rights at 13 NASCAR tracks and title sponsorship of two races, the Coca-Cola 600 in Charlotte and Coke Zero 400 in Daytona.

Pepsi has pouring rights at nine Sprint Cup tracks and holds the title sponsorship of two races, the Pepsi 500 in Fontana, Calif., and AMP Energy 500 in Talladega, Ala.

Gatorade, owned by Pepsi, also sponsors non-points preliminary races in Daytona and has rights at all International Speedway Corp. tracks and Dover, Del., because of a deal as the sports drink partner.

NASCAR's growth has made it an important marketing platform for both Coke and Pepsi, said John Sicher, editor and publisher of Beverage Digest.

Pepsi bottlers cheered last year when Pepsi landed Earnhardt for its AMP brand. "Rarely have I heard more enthusiasm from bottlers about a promotional tie-in," Sicher said.

NASCAR's foothold in the South, known for big sales of carbonated soft drinks, also helps, he said.

"The consumption pattern of the consumer they want to reach and the areas where NASCAR is most popular work very well together," Sicher said.

Coke and Pepsi both have aggressive plans for capturing the NASCAR audience.

The long racing season, February to November, and the loyal fan base make NASCAR significant, Perez said.

"When you look at the consumer, the racing fans, they are some of the most loyal fans in sports," Perez said.

"We know that they truly believe the sponsors help make the sport happen for them and for the drivers, and they reward the corporations with loyalty."

NASCAR also provides a grass-roots sales boost that sets it apart, said Pepsi's Santana.

"When the race is in town, you know you're going to get a big volume hit," Santana said. "It's almost like everybody gets their own personal Super Bowl."

Coke and Pepsi, though, have different approaches to winning customer loyalty.

Coke marketing executives stress the overall NASCAR experience, having ties to the series, the tracks and the drivers. Coke targets NASCAR fans at stores before the race begins, as well as at the track. As they exit the race, Coke will have samples to hand out.

This total marketing approach helps Coke connect with fans, said Ben Reiling, director of motorsports for Coca-Cola North America.

"As long as you create the right relationship with them and the right dialogue, they're willing to take you into their households," he said.

Pepsi's focus is clearly on the drivers. It has fewer drivers than Coke, but arguably the two best-known. Gordon helped broaden NASCAR's appeal in the 1990s. Earnhardt has won NASCAR's Most Popular Driver award for five straight years.

"If you want to impact sales, you have to get them while they're pulling into a Wal-Mart or K-Mart or Publix," Santana said. "The way you do that is with drivers."

Drivers are important, but Coke also values the track deals, Perez said.

Pouring rights are not just about selling Cokes at the track, she said. They also enable Coke to put up signs, work with the concession stands on promotions and pass out new product samples.

Coke would even like to expand its track deals, Perez said. It would like to bump Gatorade from its track partnerships, which allow Gatorade to be served as a sports drink at tracks even where Coke has the soft drink and bottled water rights.

"We respect the fact that their contracts were in place," Perez said. "You can't do anything about that today, but you never know what the future holds."

UNDER THE RIVALRY'S HOOD

Here's how Coca-Cola and archrival PepsiCo hope to run circles around each other in trying to tap racing's fans:

COCA-COLA CO. VS. PEPSICO

COCA-COLA CO.

Races: Coca-Cola 600 in Charlotte, Coke Zero 400 Powered by Coca-Cola in Daytona.

Pouring rights: 13 Sprint Cup tracks

Drivers: Coke: Tony Stewart, Kevin Harvick, Jeff Burton, Denny Hamlin, Mark Martin, Greg Biffle, Elliott Sadler, Jamie McMurray, Bobby Labonte, Michael Waltrip, Clint Bowyer, David Ragan, Kyle Petty and Dale Jarrett (retired). Terry Labonte will fill in for Petty this weekend; Vitaminwater:Carl Edwards; NOS energy drink: Kyle Busch.

PEPSICO

Races: Pepsi 500 in Fontana, Calif., and AMP Energy 500 in Talladega, Ala. PepsiCo also sponsors the Gatorade Duel I and II non-points races in Daytona.

Pouring rights: 9 Sprint Cup tracks. Gatorade has rights at all ISC tracks and Dover, Del., under a sports drink marketing agreement.

Drivers: Pepsi: Jeff Gordon; AMP Energy: Dale Earnhardt Jr.; Gatorade: Jimmy Johnson, Matt Kenseth and Ryan Newman; No Fear energy drink: Boris Said.