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Ricky Stenhouse Jr. and Elliott Sadler have fought tooth and nail for the Nationwide Series championship all year long, and now it comes down to this weekend's season-ending race at Homestead- Miami Speedway to decide the title.

Stenhouse is seeking to become the sixth different driver to win back-to-back championships in NASCAR's second-tier series. He presently leads Sadler by 20 points, which is the same point-separation between Sprint Cup Series title contenders Brad Keselowski and Jimmie Johnson.

No driver other than Sadler or Stenhouse has led in the Nationwide point standings this season. Sadler has sat no lower than second in the rankings, but his current 20-point deficit is his largest since May when he trailed Stenhouse by 34 points.

Rookie Austin Dillon, who is Sadler's teammate at Richard Childress Racing, is the only other driver who remains in contention for the championship. Dillon is 25 points out of the lead.

Stenhouse will clinch the championship if he finishes 16th or better at Homestead. The Roush Fenway Racing driver is also guaranteed of the title if he finishes 17th or higher after leading at least one lap or places 18th or better with the most laps led.

"It's not even close to being over," Stenhouse said. "We still have to make sure we do everything at Homestead. It's gonna be tough, because I'm gonna have to not push the limits as much as I like. I like going for race wins too, so it's gonna be a fine balance there, because I want to win that race and win the championship all at the same time."

Those drivers who have won successive championships in the series include: Sam Ard (1983-84), Larry Pearson (1986-87), Randy LaJoie (1996-97), Dale Earnhardt Jr. (1998-99) and Martin Truex Jr. (2004-05).

"We started the year off counting points as soon as we started, and it would mean a lot to me to go back-to-back," Stenhouse said. "I think as a race car driver you come out to win championships. You want to win races, but championships are what last for a long time. Last year was special. It felt like we didn't have a dominant year, so even though it was still a championship, it didn't feel like a championship year. This year has felt like it's been a championship year, so it would be huge."

Stenhouse and Sadler were tied in points heading into last Saturday's race at Phoenix, but Sadler finished 22nd after he was involved in a multi-car crash in the closing laps. Stenhouse posted a third-place run.

Sadler will compete in his last Nationwide race for RCR. He announced earlier this year that he is leaving Childress' team at season's end. It is widely rumored that Sadler will join Joe Gibbs Racing for the 2013 season.

"It's hard to believe that it is the last race of the season already," Sadler said. "This team has been great to work with. I love the determination and the heart each member of the team has, and although we head to Homestead with a deficit, we are not out of this championship. We will fight until the end. We have to finish off what we started, and we are as prepared as we need to be to go out there and make it happen."

Neither Stenhouse nor Sadler has won a previous Nationwide race at Homestead. Stenhouse has finished second and fourth in his first two starts there, while Sadler has placed no better than fifth in his six races at this 1.5-mile racetrack. Dillon will compete in a Nationwide event there for the first time.

Forty-eight teams are on the preliminary entry list for the Ford EcoBoost 300.

Series: NASCAR Nationwide. Date: Saturday, Nov. 17. Race: Ford EcoBoost 300. Site: Homestead-Miami Speedway. Track: 1.5-mile oval. Start time: 4:30 p.m.(ET). Laps: 200. Miles: 300. 2011 Winner: Brad Keselowski. Television: ESPN. Radio: Motor Racing Network (MRN)/SIRIUS NASCAR Radio.