Dale Earnhardt Jr.'s Showdown chances

Paul Menard, Brad Keselowski and now, Marcos Ambrose, have officially punched their Summer Showdown tickets. In other words, they just need a win at Atlanta to have an extra million dollars in their pocket and earn a million each for a charity and the lucky fan who picks them to win.

Who has the best chance to join them this week at Michigan? My first instinct is Denny Hamlin, who won at Michigan back on June 19. He's finished outside the top 15 the past three weeks, and he's a guy who really needs a win to secure his spot in the Chase. His team is getting bumped back in points, and they're due to bounce back.

Carl Edwards is another guy who has been running well all year and has the potential to do some damage at Michigan. Roush cars finish strong on these bigger tracks. I think their engine packages are a little bit superior and that definitely plays to their strength.

On the other side of the Showdown pool is Dale Earnhardt Jr., whose last win came at Michigan back in June 2008. It's a wide track, and he's one of those guys who'll go wherever he needs to in order to pass -- whether that's all the way at the bottom or all the way at the top. And I mean all the way to the top. But it'll be hard for him to beat Hamlin and Edwards. Earnhardt had the performance earlier in the year but his team lost their mojo. I don't know where they lost it, but I haven't seen it in a while. And though I expect him to run well, I don't see him bringing the mojo back enough to break this winless streak.

Though the Chase is in the forefront, the Summer Showdown bonus is definitely on driver's minds. It's a great incentive and it adds to this fun environment we're starting to see week in and week out. You can see guys driving harder and doing anything and everything for a win.

Andy Petree, a NASCAR veteran who has been a driver, car owner and two-time NASCAR Sprint Cup-winning crew chief for the late Dale Earnhardt, is an analyst for ESPN's multi-platform NASCAR coverage.