Jimmie Johnson is a realist -- he knows, sooner or later, another driver will end his streak of consecutive Sprint Cup championships that reached five with his 2010 title run.

"I have a lot invested in this, and I'd love to see the streak stay alive," Johnson said, "but at the same time, I've won five, and at some point we're going to lose one."

Don't read that as a concession speech. Johnson is just as committed to winning a sixth championship as he was to winning his first in 2006.

"I know I'm going to work and give 100 percent -- and this team is -- and it is what it is," Johnson said.

Johnson is at his best in the Chase, NASCAR's playoff. He and crew chief Chad Knaus have mastered the process of pacing themselves during the first 26 races and peaking for the final 10 that decide the title. If another driver is to end Johnson's streak, he and his team will have to be even better.

Here are the six favorites who could stop Johnson's drive for six championships.


Kurt Busch

There's no one in the Sprint Cup garage who would like to dethrone Johnson more than Busch, who has adopted the slogan "Anybody but the 48" as his Chase mantra.

Busch and Johnson have had issues in the past, most recently over the weekend in Richmond. Busch, who won the title in 2004, is the only driver other than 2005 champ Tony Stewart and Johnson to have won a championship under the Chase format -- in what can rightfully be called the Johnson Era.

Because there's a rivalry between Busch and Johnson, however, doesn't mean Busch hasn't observed the methodology Johnson and Knaus have adopted in fashioning their five consecutive championship runs.

"You just have to be good in all areas, like they have been," Busch said. "You need to be an A-plus. When Chad sees things that aren't an A-plus, he makes big changes. That's where the rest of us need to be there with 'em. So it's engine department, chassis, aero -- you have to have it all."

That Busch is in position to fight for a championship represents both a dramatic turnaround and a vindication. Early in the season, when the Penske Racing Dodges weren't handling to his liking, Busch called out team engineer Tom German on the team radio and questioned the direction German had established for the setups of his cars.

Shortly thereafter, German departed to pursue an advanced degree at MIT, and -- coincidence or not -- the performance of the Penske cars improved markedly, enough to solidify Busch's position in the Chase and to provide a coattail effect for teammate Brad Keselowski, who picked up three wins and made the Chase for the first time.

Busch also has observed Johnson's road map over the last 10 races of his five championship seasons. Johnson has won 19 of the 70 Chase races -- at least one each year since the inception of the format. Busch believes a combination of consistent performance and wins is the path to a title.

"I don't think you have to win often," Busch said, "but you do have to win."

Where Busch will be strong: New Hampshire, Kansas, Homestead

Where Busch will struggle: Martinsville


Kyle Busch

This Chase will be different for Busch, who has been much more successful in proving Murphy's Law than in winning a Cup championship.

Emblematic of that was 2008, when Busch won eight of the first 22 races, entered the Chase as the top seed and promptly saw his title hopes trashed by a succession of mechanical failures.

Married on New Year's Eve and having developed a trust with crew chief Dave Rogers, Busch brings a newfound maturity and an evenhanded approach to this Chase -- an outlook that makes him a serious threat to unseat Johnson.

"He should have gotten married two years ago," Joe Gibbs Racing president J.D. Gibbs quipped last month at Michigan after Busch's fourth win of the season. 

Mistakes have haunted Busch in the past. Mistakes are precisely what he plans to avoid this year.

"The biggest thing is just being able to stay competitive through the final 10 races," Busch said. "Even the Talladega race -- you're going to try as hard as you can to stay out of trouble and at least get through there with a top-10.

"You can't have motor issues, you can't have pit stop issues, you can't have sway bar arms falling off -- everything that I've ever had in the Chase."

Getting off to a strong start in the Chase will be critical. For the first time since its inception in 2004, the 10-race playoff will start somewhere other than New Hampshire. This year it opens at Chicagoland, a track where Busch has a win and a third in six starts but has finished 17th and 33rd in his past two races.

If Busch can get through Chicagoland and New Hampshire the following week in good shape -- and can avoid trouble at Talladega -- he'll be in a strong position to battle for the championship. As is the case with Johnson, the balance of the schedule plays to Busch's strengths.

Where Busch will be strong: Dover, Martinsville, Phoenix

Where Busch will struggle: New Hampshire, Talladega


Carl Edwards

Throughout 2011, Edwards has dominated the headlines -- but not, by and large, because of his performance on the race track. That performance, mind you, has been excellent. Edwards had held or shared the points lead after 16 of 22 races until his car had electrical-system issues in August at Michigan.

Nevertheless, Edwards made more news for his protracted contract negotiations. Joe Gibbs Racing made a powerful pitch to lure Edwards from Roush Fenway Racing, but Edwards opted to stay put.

Though he forgoes the services of an agent and negotiates the minutiae of his contracts himself, he was able to keep his racing and his business life in separate compartments -- at least to the extent that he could field offers on the one hand and still drive with his usual controlled aggression on the other.

"This sport has so many different variables and so many different things going on that I think anybody who's successful in this sport has to be able to put everything else aside when they get in the race car and focus on racing," Edwards said. "I don't feel like I'm any better than anyone else at that, but it's something that you have to learn to do.

"For me, it takes about all I've got mentally to do it, and while I'm in that race car, that's all I think about -- and it's really fun." 

That focus will help Edwards as he tries to unseat Johnson. Edwards also has something else on his side that he didn't have until the end of last season -- raw speed. Midway through the 2010 campaign, RFR corrected problems with its computer simulations and began to improve the handling of the organization's cars. Edwards won the final two races.

"I feel like we've shown this year that we can lead the points," Edwards said. "I feel like our team is strong, and we're able to apply our experiences. And really, we're just faster. We're faster this year than we have been for a long time."

Where Edwards will be strong: Dover, Kansas, Texas, Phoenix, Homestead

Where Edwards will struggle: New Hampshire, Martinsville


Jeff Gordon

If old people can't drive, they certainly can't race.

If Gordon wins the championship this year, he will be the first driver on the wrong side of 40 to do so since Dale Jarrett in 1999. In NASCAR's modern era, only Jarrett, Dale Earnhardt, Bobby Allison and Richard Petty have won championships in their fifth decades.

Recently, the sport has been dominated by young drivers, many of whom are where they are largely because of the path Gordon blazed in the 1990s.

But that's ancient history. What about the present -- can Gordon end his nine-year title drought, win championship No. 5 and thereby restake his claim as one of the best ever, alongside Petty, Earnhardt and now his (no longer young) protege Johnson?

If Gordon races like he did in the first 12 races of the season, no. If he races like he has since then, yes.

Gordon started to turn his season around after a terrible performance at Texas. In that race, his car was so bad that crew chief Alan Gustafson revamped the way he set up future cars for Gordon. The new approach has worked. Gordon finished 23rd at Texas and has finished worse than 20th only once since, and that was because of a crash at Richmond in April.

From race No. 13 on, Gordon has produced championship-caliber results. When Gordon has a fast car, the results show it, and Gustafson has been building consistently fast cars. Gustafson is considered one of the best crew chiefs in the garage. The more he and Gordon work together, the better they get. Even in their first year together, they appear comfortable enough to be title contenders. "Every week I go into those debriefs and come away thinking that we're going to wear them out this weekend," Gordon said.

That's how Gordon did it in the good old days, and he has shown flashes of it again this season. The key for him will be whether he can keep it up for the full 10 races in the Chase. That's a long time to sustain excellence at any age.

Where Gordon will be strong: Chicagoland, Kansas, Martinsville, Phoenix

Where Gordon will struggle: Charlotte, Texas


Kevin Harvick

To win the Chase, Harvick needs one thing.

It's not a fast car; he already has one of those. He has four wins this season and has finished on the lead lap in 22 of 26 races, which means he has the speed to run up front and the consistency to avoid bad finishes, both of which are mandatory in the Chase.

It's not a solid crew chief, a fast pit crew or ample driving skill -- he has all of those, too. Harvick doesn't have a weak spot; he's good on flat tracks, short tracks, intermediate tracks and restrictor-plate tracks (especially restrictor-plate tracks). The track he despises most is Charlotte, and he won there in the spring. He says his No. 29 team is stout top to bottom and will win or lose the championship based solely on performance.

So if it's not a fast car or a solid crew chief or a fast pit crew or ample driving skill, what does he need?


He needs to pick a fight, cause a wreck, point out the unworthiness of some other driver's mother. He has said it many times: He thrives on controversy.

It seems to focus his concentration. Anger, even if it's manufactured, makes him get up on the wheel a little bit more. At Darlington this year, he reached into Kyle Busch's car to try to sock him one. Harvick was fined and placed on probation by NASCAR, which has roughly the same effect as you putting him on probation. Except for this: In the next four races, Harvick finished 10th, first, 11th and fifth.

Kyle Busch was his target this season (and last), but Busch is hardly the only one to battle with Harvick. He has criticized or feuded with drivers up and down the standings. He called Carl Edwards a pansy, tried to choke Greg Biffle, got in a shoving match with Juan Montoya, called Kurt Busch a "cocky, arrogant punk," and on and on.

Where Harvick will be strong: Chicagoland, Talladega, Homestead

Where Harvick will struggle: Dover, Charlotte


Matt Kenseth

A Kenseth championship would bring NASCAR full circle. NASCAR started the Chase format in response to Kenseth's championship in 2003, when he won one race but captured the title because nobody else could do better than his 10.2 average finish.

Kenseth's Roush Fenway Racing cars should be fast enough for him to stay in the hunt this time around. He's so steady at the wheel that he'll never overdrive them or take unnecessary risks. The Chase rewards consistency and punishes poor finishes. Kenseth will avoid poor finishes. But the consistency has to be better consistency than he has mustered so far. He needs to string together top-fives, not top-10s.

"You always want to do better and improve," Kenseth said. "You want to be on your game the last 10 races when it really counts, but overall, it has been a good season for us."

If he's on his game in those last 10 races, it will become a great season and you probably won't even realize it until the end. If Kenseth beats Johnson, here's how it will go: Kenseth will be in the middle of the pack for seemingly the whole Chase. His cars will be good but not great. He will hit his marks time after time, lap after lap, but he will never make a spectacular save or barrel his way to a win (which is not to say he won't win a race). Finally, when the Chase nears its end -- poof, there he will be, out of nowhere. That's how he runs races, that's how he runs seasons, that's how he does everything. 

Where Kenseth will be strong: Chicagoland, Dover, Charlotte, Texas

Where Kenseth will struggle: Kansas, Talladega, Homestead