Let the 10-week madness in the Sprint Cup Series begin.

Sunday's 400-mile race at Chicagoland Speedway kicks off the 2012 Chase for the Sprint Cup championship. It's the second straight year Chicagoland hosts the opening round in the playoffs. New Hampshire started the Chase each year from 2004-10.

Just 12 points separate top-seed Denny Hamlin from 12th-place Jeff Gordon.

Tony Stewart begins his title defense only three points in back of Hamlin. When the series came to Chicagoland one year ago, Stewart started the Chase in the ninth seed and had yet to win a race during the season. He had struggled during the summer months and just squeaked into the playoffs.

Delayed one day due to rain, Stewart prevailed in the Chase-opener at Chicagoland. He gambled on fuel in the late going and held off Kevin Harvick during the closing laps to claim his first victory of the season. Stewart won again the following weekend at New Hampshire.

Stewart went on to win at Martinsville, Texas and the season-ending race at Homestead. He finished the Chase in a points tie with Carl Edwards but claimed his third championship in NASCAR's premier series by virtue of his five wins.

"It's hard to predict what's going to happen," Stewart said. "I wouldn't have predicted last year was going to end up like it did, and I wouldn't have predicted this year was going to be the way it is right now. I'm just trying to take it a race at a time right now."

Stewart finished fourth in last Saturday night's race at Richmond and ended the regular season 10th in the point standings. With victories at Las Vegas, California and Daytona earlier this year, Stewart earned nine bonus points to start the Chase.

But Stewart has concerns heading into the final 10 events. He had finished no better than 19th in four straight races before ending his streak of bad luck with a top-five run at Richmond.

"I'll be honest; I'm not happy with any part of my program right now," he admitted. "We have a lot of work to do."

Stewart is the only driver in the postseason that has won at every Chase track. In fact, he has won at all tracks on the current Sprint Cup schedule, except Darlington and Kentucky. The series ran at Kentucky for the first time last year.

Stewart leads all drivers with three victories at Chicagoland. His other wins there came in 2004 and '07.

Gordon, Harvick and Dale Earnhardt Jr. are the only other Chase drivers who have won at Chicagoland in the past. Harvick won the first two races there from 2001-02. Earnhardt Jr.'s victory at this 1.5-mile track came in 2005, while Gordon's win there occurred in 2006.

Earnhardt Jr. and Harvick qualified for the Chase by finishing the regular season in the top-10 in points. Gordon earned his way into the playoffs with the second and final wild card spot.

"You want to come out of the gate strong and get the best possible result you can," Gordon said. "If that's a win, great. If that's fifth, great. A lot can happen during the Chase. To me, 10 weeks is a lot of racing."

Hamlin is hoping to return to his winning ways at Chicagoland. He had been on roll by winning at Bristol and then Atlanta. Hamlin put on a dominating performance for most of the race at Richmond, leading 202 of the first 300 laps. But pit strategy during the final 100 laps put him out of contention to win, as he finished 18th.

"Now it's time to put your game face on and see what you got," Hamlin said. "We're excited about going to Chicago and hopefully getting a good kickoff to the Chase."

Hamlin's best finish in six races at Chicagoland is fifth, which came in 2009. He finished 31st there last year.

"When I start my engine for the very first Chase race, I'm not thinking about Homestead, and I'm not thinking about a championship. I'm thinking about that race, and that's the attitude I'm going to have," Hamlin said.

Forty-seven teams are on the preliminary entry list for the Geico 400.

Series: NASCAR Sprint Cup. Date: Sunday, September 16. Race: Geico 400. Site: Chicagoland Speedway. Track: 1.5-mile oval. Start time: 2 p.m.(ET). Laps: 267. Miles: 400.5. 2011 Winner: Tony Stewart. Television: ESPN. Radio: Motor Racing Network (MRN)/SIRIUS NASCAR Radio.