MARTINSVILLE, Va. --- Martinsville Speedway is the place where Jimmie Johnson started his four-race winning streak a year ago on his way to his second consecutive championship.

As rain fell Friday and wiped out qualifying, putting the points-leading Johnson on the pole for the second week in a row, the drivers closest to him in the Chase for the Championship had to wonder if a third title in a row was a foregone conclusion.

"I don't know where Jimmie gets his horseshoes," Carl Edwards said, "but he's got amazing luck, and they do everything right, so we just have to hope for something strange to happen."

Edwards and everyone else know, though, that time is running out.

After today's Tums Quikpak 500 on NASCAR's shortest, trickiest track, only four events remain on the schedule, and Johnson is the defending champion in three of them.

Tony Stewart, who has won two championships himself, said Saturday it's difficult not to look at what Johnson has achieved over the past three seasons and simply marvel.

"It's hard to win it once," Stewart said of the championship, which he won in 2002 and '05. "To win it two years in a row is extremely hard, and to just be in a position where you have the opportunity to try and win it three years in a row is unbelievable."

But Johnson hasn't opened a prohibitive lead by any stretch. At least not yet.

Jeff Burton is second in points, 69 behind, and Greg Biffle is third, another 17 back. After that comes Edwards, whose six victories for the season are the second most in the series, but who has finished one spot behind Johnson twice in the first five Chase races.

"I think it's 35 points a race we have to make up or something, and that's assuming that Jimmie doesn't have any bad luck," said Edwards, who has finished 29th and 33rd in the last two weeks. "I feel like all we can do now is just go race as hard as we can."

Burton and then Jeff Gordon have entered this race the past two seasons with the points lead and need to look back only to last year to see that Johnson's advantage is not insurmountable.

Gordon led Johnson by 68 points in 2007 and seemed on the road to his fifth title before his Hendrick Motorsports teammate eventually won by 77 points, a swing of 145.

The bad news is that Johnson has become a comfortable front-runner.

"In the past, I've probably wanted to be in a different position and be a close second or something and not have to have the pressure," he said. "But this Chase, this team, the confidence we have in ourselves and what we've developed over the years and the experience we've been through, that has made me much more comfortable with where we are today."