AVONDALE, Ariz. — Just when Carl Edwards seemed to have Jimmie Johnson on the ropes, the two-time defending NASCAR champion delivered the knockout punch.

Johnson moved inches away from his record-tying third consecutive Cup championship with a dominating victory today at Phoenix International Raceway, where he led a race-high 217 of the 313 laps to deflate Edwards' title hopes.

Johnson heads into next week's season finale up 141 points over Edwards and needs only to finish 36th or better to join Cale Yarborough (1976-78) as the only drivers in NASCAR history to win three straight Cup titles.

"This is what I've worked my whole life for," Johnson said in Victory Lane.

The win was his third straight at Phoenix, and had Edwards on the edge of conceding after his own fourth-place finish.

"It's still possible," Edwards sighed. "It's not probable."

No, it's not. Not with the way Johnson is running.

Johnson has made a mockery of Chase for the championship format, reeling off 14 wins in the 49 races since NASCAR adopted the format in 2004. He contended for the title in 2004 and 2005, only to come up just short both seasons.

He's on the verge of joining Yarborough, David Pearson, Lee Petty and Darrel Waltrip as a three-time champion. Jeff Gordon, his Hendrick Motorsports teammate, has four titles and Dale Earnhardt and Richard Petty won a NASCAR-record seven.

Johnson has done it in dominating fashion, particularly this year: he's finished in the top 10 in seven Chase races and his lowest finish was a sub-par 15th last week at Texas.

Edwards won at Texas, his second straight victory, to take a bite off of Johnson's lead. Then Johnson struggled through Saturday's final practice session, and suddenly looked vulnerable. But crew chief Chad Knaus worked with Johnson late into the night to figure out a better setup and strategy, and the duo had the field covered from the start on Sunday.

"Jimmie stepped up," Knaus said. "We came here with something a little bit different than what we ran in the past. It worked great for qualifying, but not in the race. Jimmie brought a lot to the table in pointing things out to me, we put a different setup in the car, and it was fast all day."

With a crowd of friends — including professional baseball players Brian and Marcus Giles — watching from his pit box, Johnson started from the pole but gave way to Jamie McMurray on the first lap. He didn't take the lead until Lap 81, but was never challenged from there.

McMurray briefly moved out front again after a round of late pit stops, but Johnson blew past him in Turn 2 of a restart and was hardly challenged again. Kurt Busch made a brief run at him in the closing laps, but graciously settled for second.

"We just got beat, and we got beat by something special. He's doing something pretty special," Busch said. "It's really a privilege to finish second to him today."

McMurray was third, followed by Edwards, Denny Hamlin, Dale Earnhardt Jr., Kevin Harvick, Kyle Busch, Jeff Burton and David Ragan.

With the win, cash-strapped General Motors wrapped up its 32nd NASCAR manufacturer's championship.