PHOENIX—Chase Elliott was supposed to be the star during his season as both NASCAR’s reigning champion and its most popular driver. He wasn’t even the top guy at his own organization. Beat all season by Hendrick Motorsports newcomer Kyle Larson, Elliott gets a final shot Sunday to defend his run as NASCAR’s champ. The star teammates are trying this weekend to emerge as the best in NASCAR—and earn bragging rights at Hendrick—as they race for the championship at Phoenix Raceway in a winner-take-all finale. Yes, Joe Gibbs Racing teammates Denny Hamlin and Martin Truex Jr. also are in the final four. But who comes out as the top dog at Hendrick, winner of 16 races this year and NASCAR’s winningest team, is one of the more intriguing layers of the first sold-out finale since the race moved to Phoenix last year. Elliott last season not only advanced to his first …