HAMPTON, Ga. -- Over? If the pundits have declared that the 2008 Sprint Cup championship chase is over, the key players remain unconvinced.

Despite being 149 points behind with four races remaining, Greg Biffle hasn't conceded the championship to Jimmie Johnson just yet. Neither have Jeff Burton (152 points out) or Carl Edwards (198 points in arrears).

“

We're gonna have to have four flawless races. Obviously, if you do the math, 149 points divided by four, that's obviously what we need to pick up per race ...

”

GREG BIFFLE

And quite honestly, despite a number of "it's all over but the shouting" stories and columns this week, Johnson wasn't preparing any kind of coronation ceremony at Atlanta Motor Speedway, as a steady mist interrupted practice and qualifying for Sunday's Pep Boys Auto 500.

OK, so Johnson hasn't finished out of the top 10 since Bristol, and hasn't finished worse than 14th in a Chase race in more than two years. But he might be the last person in the garage area who thinks a third consecutive championship is sewn up.

"I still feel like we have to stay on edge," Johnson said. "There are long races where you can have mechanical issues, you have a lot of cars on track, a lot of times on and off pit road, and there is a lot of risk in our sport for having a bad race.

"And it's tough to link together 10 races without any trouble. So I'm a realist when I look at that and think that we went through Fontana to Richmond and then started the Chase. We're hopeful of going through 14 races without any issues and that's a tough thing and high expectations."

With a lead like Johnson has on the rest of the field, you might think he might feel a little comfortable. But that's not the case.

"I still stay scared and I've used that term quite a bit," Johnson said. "I just want to make sure we're not getting into a comfortable mindset and put our guard down and I make a mistake or the team makes a mistake. The things that are going to be out there, we can't control. And if that hits us, we'll come back next week and hopefully be able to take care of business."

Of course, Biffle knows the challenge of catching Johnson by the time the checkered flag falls at Homestead is daunting, but don't confuse that with giving up. In his opinion, it only takes one mistake, and suddenly he -- and perhaps Burton and Edwards -- is back in the hunt.

"We have to finish well the next four in order to win it and we know that he's gonna have to have a little slip," Biffle said. "That could be not running well here, maybe getting a lap down somewhere.

"He was a lap down at Talladega. He was a lap down somewhere else or not running well and ended up coming back at the end, so it's possible. It's certainly possible. We're just gonna do the best we can and see where he ends up at the end of the day."

What Biffle can't afford is a misstep.

"We're gonna have to have four flawless races," Biffle said. "Obviously, if you do the math, 149 points divided by four, that's obviously what we need to pick up per race -- it's got to be those positions or more -- but we know if he slips that we have to capitalize and if he has a problem, that we have got to finish well in that event."

At this point, Burton's focus is less on the No. 48 Chevrolet and on his own performance.

"All we can do is control what we do," Burton said. "We're here this weekend to just control what we do. We got ourselves in a situation last week where stuff piled up on us and we ended up making not a great day even worse and those are the kind of things that just kill you. We've got to find a way to rebound from that."

Johnson could have an insurmountable lead when the circuit hits Homestead, Burton admits. But even when people were conceding the title after Johnson built what appeared to be an overwhelming advantage last season, Burton said Jeff Gordon still had a chance.

"Let's be clear, the fact of the matter of last year was that Jimmie Johnson went into Homestead with a 50-something point lead on Jeff Gordon," Burton said. "Gordon waved the white flag, if you remember, and said the race is over, but one hiccup by the No. 48 car and the race wasn't over."

So how does Johnson view the next four races? He hopes for the best, but prepares for the worst. And the key for him is to make sure if something happens Sunday, one bad race doesn't affect his confidence.

"I try to look at the worst-case scenario, and if we leave here with 43rd-place points, who has a shot and who is very good at the tracks that are coming up," Johnson said. "That is really the way I look at it.

"Again, I just try to recognize it, I feel like I have closed that chapter in my head. That way I can look forward to what my team needs to do, what I need to do in the seat. Stay focused on positive things and things that put a smile on my face instead of worrying about a negative side to it."