Racing in other series challenges Cup drivers
{{#rendered}} {{/rendered}}Kevin Harvick and Kyle Busch both have hopes of knocking off Jimmie Johnson this year, snapping his four-year championship streak and each winning their first Sprint Cup title.
Harvick, a two-time Nationwide Series champion, has made the Chase three times and is off to a great start this season, leading the points standings after four of the first six races.
Busch has also made the Chase three times - twice for Hendrick Motorsports and once with Joe Gibbs Racing - and has won more races (12) than any driver other than Johnson the past two seasons. He also won last year's Nationwide Series championship, his first NASCAR title.
{{#rendered}} {{/rendered}}Both have championship pedigrees and seem like strong contenders to knock Johnson from his perch atop the Sprint Cup Series.
But the odds are stacked heavily against them.
Why?
{{#rendered}} {{/rendered}}Because both Busch and Harvick have a lot of extracurricular activities going on that tend to detract from the ultimate goal.
Both like to race, and race a lot. And they both have busy racing schedules, competing in all of NASCAR's top three national touring series.
And history says that doesn't bode well for drivers looking to win a Cup championship.
{{#rendered}} {{/rendered}}Top Cup drivers have always dabbled in what is now known as the Nationwide Series on the side, and many are dominating that series today.
But very few have ever won a Cup championship while running a heavy schedule in another one of NASCAR's top series. And it's been 14 years - Terry Labonte in 1996 - since anyone has done it.
Only five drivers have ever won Cup championships while also racing regularly in the Nationwide Series, and only two of them ran a heavy schedule in both series.
{{#rendered}} {{/rendered}}Darrell Waltrip ran just two races in that series when he won the 1982 Cup championship, and only eight when he won it again in 1985.
Dale Earnhardt ran nine or more Nationwide races - but never more than 14 - each season between 1986 and '94, when he won six of his seven Cup championships.
But the driver who stayed busiest during his championship season was Labonte, who ran 18 Nationwide races when he won the 1996 Cup title.
{{#rendered}} {{/rendered}}Mark Martin came close, finishing second in Cup points three times while running a heavy Nationwide schedule (he ran just one Nationwide race last year when he finished second in Cup points).
Only two drivers in recent years have accomplished the feat.
Tony Stewart ran 12 Nationwide races while winning the 2005 title, and Matt Kenseth ran 14 while winning the '03 championship, but they are the exception.
{{#rendered}} {{/rendered}}Several drivers in recent years have had strong Cup seasons while also running in the Nationwide Series - Busch, Harvick, Carl Edwards, Greg Biffle, Matt Kenseth, Clint Bowyer - but none have won a Cup championship.
Johnson, meanwhile, continues to dominate the Cup series with intense focus on that series and that series alone.
And a year ago, the top four finishers in the Chase ran just one (Martin) Nationwide race between them.
{{#rendered}} {{/rendered}}Johnson and Jeff Gordon ran very few, if any, Nationwide or Truck races during their championship years in Cup.
Gordon, for instance, didn't run any Nationwide races when he won the 2001 championship. And though he came through the Nationwide Series, he didn't run any races in that series during his Cup championship seasons in 1995, '97 and '98.
Johnson didn't run any Nationwide races when he won his fourth Cup title last year, and has run a total of just 10 during his four championship seasons.
{{#rendered}} {{/rendered}}Even Bobby Labonte and Dale Jarrett, two longtime veterans of the Nationwide Series, didn't run Nationwide races in the years they won the Cup championships in 1999 and 2000.
Complicating matters for Busch and Harvick is that they are not just racing in those series. They both own their own teams, Busch in the Camping World Truck Series and Harvick with teams in both the Nationwide and Truck series.
While running those races and running those teams might not prevent them from winning Cup races - it hasn't so far - it certainly takes away just a bit of their focus on NASCAR's top series.
{{#rendered}} {{/rendered}}Not only do the rigors of such a busy schedule take its toll physically, but the mental strain of preparing for and competing in so many races has to eventually become a distraction, particularly as competitive as the Sprint Cup Series is today.
The headache of owning and operating a team, which the 24-year-old Busch is doing for the first time, has to be a bigger distraction and a drain on a Cup drivers' time and mental focus.
And, historically, it's even more difficult to win a Cup championship while owning your own team in another series.
{{#rendered}} {{/rendered}}Waltrip, Earnhardt and Labonte each owned their own Nationwide cars when they won Cup championships, but it was a different era then. It didn't take as much effort or as many people to run a Nationwide team. Running the Saturday race was almost like a hobby, and didn't require the time and intense focus that it does today.
Of all the Cup drivers running in multiple series today, only Busch and Harvick own their own teams.
Edwards is running the full schedules in Nationwide and Cup again this year, and desperately wants to become the first driver to win both championships in one season.
{{#rendered}} {{/rendered}}If he does it, it would be a monumental feat.
Just winning a Cup championship while running part-time in the Nationwide Series have proven to be difficult enough.
Two years ago, Edwards, Biffle, Harvick and Clint Bowyer each finished in the top five in Cup points while running a heavy Nationwide schedule, with Edwards winning nine races and challenging Johnson for the championship.
{{#rendered}} {{/rendered}}So, it's not out of the question that Busch or Harvick can pull it off.
But history says the odds are against them.