MILWAUKEE - For NASCAR, this is still spring training, that glorious time when bright sunshine fuels rampant optimism and no one is even a single point out of the lead of the standings.

Look quickly. By the time this weekend is out and qualifying has been completed for the Feb. 20 Daytona 500, the off-season will officially be over and the race will be on for the 2005 Nextel Cup Series championship.

During the next 10 months, that optimism will either be backed up with victories and top-five finishes and a place in the Chase for the Championship or snuffed out by slow setups, broken parts, bad luck and bent race cars.

Along the way, fans will find out:

Who can adjust most quickly to new aerodynamic specifications that have made the cars trickier to drive and new rules that essentially eliminate special qualifying setups for most race weekends.

Whether 2004 champion Kurt Busch can benefit from the lessons learned by teammate Matt Kenseth and his crew during the defense of their '03 title.

What changes to crews and teams will pay off in turning also-rans into winners, challengers into contenders and, perhaps, a contender into a champion.

Which of the retiring high-profile veterans can go out on top, the way all of them would like, and who, among the newcomers and rising stars, will take their places.

With a year to get used to the "Nextel Cup" name and Chase format, 2005 dawns with less fanfare than 2004. But this would not be NASCAR without a few twists, and the sanctioning body has provided several of significance.

Gone is the "provisional" system of awarding a few starting spots based on the standings for those who couldn't qualify for a race on speed. Now, the top 35 in owners' points are automatically in each race, and there's no such thing as running out of provisionals. Insiders view this guaranteed payday as the closest NASCAR will come to franchising.

On the performance front, NASCAR has again trimmed the height of the rear spoiler, hoping that the change, coupled with a new generation of tires, will require drivers to manage the changes in their cars' handling throughout a run and thereby enhance racing action.

"The car moves around a lot," said Jimmie Johnson, the runner-up to both Busch and Kenseth. "We've taken total down-force out of the cars to balance them out. When you're by yourself or in qualifying; you're not going to see a lot of troubles. In traffic, it's going to be more difficult than what it's been."

Two changes address both cost containment and competitive balance. A specific gear will be mandatory for each race, which should minimize high-end engine development. NASCAR also will impound cars after qualifying on Saturday on most race weekends, essentially eliminating setups designed for ultra-quick, one- or two-lap runs.

"We did that a lot in the Busch Series, and it worked fine," said Jeff Green, who looks to improve on his 30th-place finish last year with Petty Enterprises. "It's going to make some of the guys starting in the back better in a race."

Even if the changes help balance out the competition, the stronger teams tend to find advantages more quickly.

Johnson and his Hendrick Motorsports team seemed to adapt well to the spoiler during testing on intermediate tracks, and Hendrick-built Chevrolet engines powered many of the fastest cars in Daytona testing. Both bode well for Johnson in pursuit of his first title and teammate Jeff Gordon, who's shooting for No. 5.

The Ford camp-specifically Roush Racing-has produced the past two champions in Kenseth and Busch. An infusion of youth in Kenseth's team was designed to help it bounce back from post-title fatigue. Busch's remained stable, but he's not overly concerned about letdown.

"If we're looked at as a favorite, we're still gonna have that same mentality to work at our pace and to not get too excited," Busch said. "There are gonna be different people tugging at you ... and you just have to roll with the punches."

Another Roush driver, Mark Martin, is preparing for his final season, along with his longtime friend and rival, Penske Dodge driver Rusty Wallace. Martin finished third last year and Wallace a disappointing 16th.

"If we can (minimize mistakes) and have a little better racing luck, we can go out with guns a-blazin', with race wins and a championship bid to look back on when the season ends down at Homestead in November," Wallace said.