Story lines are in abundance at the beginning of every season, regardless of sport, and NASCAR has plenty with its season getting revved up with Sunday's Daytona 500.

Is this the year Dale Earnhardt Jr. breaks through and wins a championship? Does Jimmie Johnson get back to his winning ways? Can Danica Patrick finally find Victory Lane? How will Tony Stewart respond after a tumultuous season?

But those are all secondary headlines going into the season. The clear-cut, no-brainer story of the 2015 season will be Jeff Gordon.

The veteran driver has announced this will be his final full-time season of what has been an illustrious career. Gordon is a four-time champion, and helped take the sport to new heights.

"This is the last year to see our Michael Jordan," Texas Motor Speedway president Eddie Gossage said. "This is one of the greats, and he's going out when he's still competitive and has a chance to win the whole thing. I thought he really was going to win the championship last year.

"Usually you see champions stick around a little too long, or much too long, but I don't think that's the case with Jeff. He's been a transformative figure in the sport and brought it great acceptance, not just nationally but internationally. I mean, this guy hosted 'Saturday Night Live' and was considered to replace Regis Philbin. Those are the kinds of things he brought to the sport."

All of his fellow drivers understand what Gordon brought to the sport, too, and have offered similar praise.

"It's been an overwhelming experience, this whole thing," Gordon said. "When you finally make it public and then you get the reaction back, and the reactions that I saw were really humbling, and it's very cool to see people that you compete against especially, say those kind of things about you."

Gordon's farewell tour is certainly the No. 1 thing to watch in racing this season. But there's more than that as well. Here are some other storylines:

Year 2 of the new Chase

After an ever-changing format, NASCAR finally might have found something that works. The knockout-style rounds for the Chase created the desired drama and intensity as Kevin Harvick emerged victorious from what began as a 16-car field.

The drivers and teams now understand what it takes to succeed under this style, which should only add to the excitement.

Said Gossage: "It was pretty darn spectacular last year, and I think any doubters had to be won over with how it all worked out. I don't think you can get any more drama than we had."

Crew-chief carousel

Several big-name drivers have changed crew chiefs, which is essentially like a baseball team changing managers.

Dale Earnhardt Jr. (Greg Ives), Jamie McMurray (Matt McCall), Danica Patrick (Daniel Knost), Kasey Kahne (Keith Rodden) and Carl Edwards (Darian Grubb) are among almost a third of the drivers who are working with a new crew chief.

NASCAR is a win-now industry, after all, and teams are willing to make moves in order to succeed. However, some of those moves don't pan out quite as well.

Said Gossage: "It's definitely going to be intriguing. Some will work and some won't. So you may see early changes because everybody can't win. Teams are quicker to pull the trigger than they used to be — it's just part of the high-pressure nature of our sport."

Less speed?

NASCAR has made several changes to Cup cars this year, such as lowering the spoilers and introducing tapered spacers that in part cut horsepower from 850 to 725. So, yes, an experienced fan will likely notice lower speeds down the straightaways.

But the speed lost on the straightaway could be made up on the turns because of a new, softer tire developed by Goodyear.

Said Gossage: "I think you'll see them be as quick or quicker as in years past. They intended to slow it down, but I've talked to drivers and they don't think it'll be slower. It'll be slower on the straightaways, but faster in turns. So it should cause some pretty good racing."

Sponsorship search

Sprint will not sponsor the Cup Series once its contract runs out after the 2016 season. That means it's an important time for the sport to showcase its value to land another lucrative deal.

The new Chase format is geared toward engaging more fans and creating more interest, and this is certainly a critical time for the long-term stability of the sport.

Said Gossage: "Right now, this has to be the most enticing sponsorship opportunity in the world of sports marketing. You can't put your name on the NFL or NBA, but you can on NASCAR racing. I don't think they're going to have a hard time finding a sponsor; it's just a matter of finding the right one. It's very much wide open."