DAYTONA BEACH, Fla. (AP) There is no ''star car'' and the headlining class is untested. Toss in the threat of steady rain, and the Rolex 24 at Daytona this weekend could very well be the ultimate endurance race of the year.
IMSA this season rolled out all new prototypes for the top class of its four divisions, and the sexy Daytona Prototype international cars from Cadillac, Mazda and Nissan have zero race experience. Questions surround the durability of the 12 entries in the prototype class, raising the possibility that the overall winner of the 55th running of the historic sports car race could come from a lower division.
The twice-round-the-clock event begins Saturday at Daytona International Speedway.
There are a total of 55 cars in the event and a stacked class in the GT Daytona division. It has 27 cars from nine different manufacturers - including Lexus, Mercedes-AMG and Acura, which are all making their Rolex 24 debut.
It's the GT Le Mans class that could pull off a very rare upset. The winner has come from the prototype class all but four times in the last 25 years, most recently in 2003. There are 11 entries in the factory-supported GTLM class, including four Fords from Chip Ganassi, who has pulled out of the prototype class and does not have his traditional car lineup of NASCAR and IndyCar stars. He's still got Scott Dixon, Sebastien Bourdais and Tony Kanaan in the race, just spread among three different entries. Bourdais teamed with pole-sitter Joey Hand and Dirk Mueller to win their class last June at the 24 Hours of Le Mans.
Bourdais isn't ruling out an overall victory from a Ganassi car, or any of the GTLM's, but knows it would be because the prototypes are unproven.
''If it rains for 24 hours, and every single P2 drops out, and four of the five (prototype challenge) cars catch on fire, then a GT Le Mans car will win the race,'' Bourdais said. ''It would take every single P2 car to have problems. I don't see anybody being very comfortable reliability wise with the P2 packages because it's so brand new.''
Although Ganassi does not have a star-studded car in the prototype class, the division does boast four-time NASCAR champion Jeff Gordon, who is driving a Cadillac with the Wayne Taylor team. He's teaming with brothers Ricky and Jordan Taylor, and Max Angelelli, who says he's retiring after this race.
Gordon ran this race once before, in 2007 with Taylor, and is looking forward to a new test.
''It was a slam-dunk for me,'' he said. ''What prevented me from doing it other years was the commitment. You really want to be in the car in December. you want to be in the car in January. You want to be in the car as much as you can, especially with this type of car being so much different than NASCAR, stock car.
''Knowing that I was capable of doing that because I was no longer driving full time and had some other responsibilities, I knew I could do it.''
Another different look in this race is that Michael Shank Racing isn't fielding a prototype car, and instead has two Acura entries in the GT Daytona class. It meant NASCAR star AJ Allmendinger couldn't be part of the lineup for the first time in years.
Shank has Ryan Hunter-Reay teaming with Oswaldo Negri Jr., Jeff Segal and Tom Dyer in one car, and Graham Rahal with Andy Lally, Katherine Legge and Mark Wilkins in another car.
Five-time winner Scott Pruett also won't contend for a record sixth overall victory because he's no longer with Ganassi and is instead launching Lexus' debut in the GTD class. He's teamed with Sage Karam, who also drove this race with Ganassi in the past, and Ian James and Gustavo Menezes.
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