Under the current Chase points system used by NASCAR for the Sprint Cup series, Mark Martin is currently in 1st place, with Jimmie Johnson following closely behind by only 10 points. As close as this race is between numbers 1 and 2, it's another 55 points back to 3rd place Juan Pablo Montoya.
All in all, from 1st to 12th place in the Chase points system, there are only 189 points separating Mark Martin from 12th place Kasey Kahne. With 8 races to go, it's still technically possible for any of the top 12 drivers in the Chase to win the championship for 2009. For the purpose of making the end of the Cup season more exciting, NASCAR has been successful in implementing the Chase points system.
For comparison, let's examine the points as they would appear under the old, pre Chase system. Thanks to Jayski.com, we are able to easily make that comparison.
Under the old points system, Tony Stewart would still be in the lead by 175 points over 2nd place Jeff Gordon. Jimmie Johnson would be in 3rd place, only 1 point behind his teammate Jeff. Under the Chase system, Tony Stewart finds himself in 5th place, and Jeff Gordon is in 8th place. Under the old points system, Mark Martin would be in 5th place, 419 points behind Tony Stewart. Since the Chase system has been in place, much the same story has been true every year.
Also under the old system, instead of 189 points separating the top 12, the points gap would be 628. This is obviously the really true advantage of the Chase; keeping the points close and putting more than 2 or 3 drivers in the run for the championship with 10 or so races to go. Other than that, I don't really know of any other advantages for the Chase system.
Drivers outside of the Chase are still on the track every week, but with obviously less TV time because they are locked out of a championship run. These drivers are still racing, however. Drivers are auditioning for new jobs, new sponsors, or just trying to prove to their existing sponsors that they can still deliver the goods, so-so season or not.
In an economy where securing and keeping sponsors has been in many ways harder to achieve than wins on the race track itself, it appears that the Chase might have outlived its usefulness. NASCAR needs all the sponsors it can get, and excluding so many from the lime light for the 'playoffs' can't sit well with sponsors whose names are on cars outside of the top 12.