Since winning the Daytona 500 to open the 2013 season, Jimmie Johnson hasn't spent much time looking back.  There have been 17 races and he's led the standings for all but two weeks in late March.

This isn't something new for the No. 48.  In 2005, he led 12 consecutive weeks before ultimately settling for fifth later in the season.  In 2006, the year of his first championship, he was in first for 22 of the 26 pre-Chase races, including a string of 16 straight weeks.

So far in 2013, he's led 12 weeks in a row and has paced the rest of the field by at least 25 points since before the STP 400 ran at Kansas on April 21.  Indeed, the five-time champion has looked nothing short of Superman as he's racked up a series-leading 11 top-10s.

But, he's not invincible.  As Eric Church quipped in his last year's release of his song Jack Daniels: "Every Superman has his kryptonite."

In Johnson's case, that appears to be Matt Kenseth.

The No. 48 has plugged away all season to build up a points lead with consistent finishes, but if the Chase for the Sprint Cup started this weekend, it would be Kenseth that claimed the top seed.  His four wins would give him 2012 points, while Johnson's three wins would place him three points back at 2009.

That doesn't seem like a huge gap to overcome, and it's not, but it proves that this season is much farther from the Year of Jimmie as his dominance might suggest.  That was evident this past Sunday at Kentucky Speedway when the No. 20 outlasted the No. 48 for the win.

Johnson led a whopping 182 of the 267 laps run, but when his car spun on a late restart, his chances of winning fell to zero.  Kenseth went on to lead the final 23 laps and claim victory.

It was fortunate that the No. 48 car was a fast machine, and Johnson raced it up to ninth to save a good day.  But, the change in outcome marked a six-point swing in the Chase's starting standings come September (assuming both drivers qualify in the top-10).

Johnson is usually in contention for the championship when it heads to Homestead.  If Kenseth were to nudge him for the Sprint Cup Trophy by, say, four points, Kentucky could be looked at as the "shoulda, coulda, woulda" for the team.

It's not the first time this season that the No. 48 has seemingly spun on its own accord.  In the Coca-Cola 600 at Charlotte, Johnson also saw a good day go for naught when he spun and finished 22nd.  He also lost the car in the second-to-last race of the season in 2012 when he was in a dogfight for the championship with eventual champion Brad Keselowski.  That day, the car appeared to lock up and slammed the wall to take him out of contention for the title.

These aren't issues reserved for just Johnson.  Every car and every driver has a malfunction or goes for a spin now and again.  It's noteworthy when it happens to Five-Time, since he's often prominently placed near the top of the standings.

With Carl Edwards stumbling to a 21st-place finish at Kentucky, Johnson only increased his points lead over second-place and now leads the No. 99 by 38.  Clint Bowyer, who sits 41 points back, is the only other driver that can mathematically catch Jimmie in one race.  Let's not hit the panic button.

Johnson remains strong, but Kenseth is more than just a hindrance to a six-pack of championships for the No. 48.  The Joe Gibbs Racing driver has recorded three, unlucky DNFs, and while the points leader has been fortunate enough not to suffer any.  That has definitely affected the No. 20's current standing in fifth place (82 points back of the No. 48).  Furthermore, Kenseth leads the series with 960 laps led; Johnson is third with 926.

With his hot start, Jimmie Johnson has established himself as the car to beat in 2013.  There's no disputing that.  But, once the points reset for the Chase, there will again be 12 drivers with a good opportunity to win this year's championship.

Matt Kenseth continues to stake his claim as a juggernaut to win the title in his first year with JGR, and it wouldn't be a surprise to see him supplant Johnson at the top of the standings when it's all said and done.