In less than three years, Tony Stewart has made a tremendous impact upon NASCAR. He drives for one of the highest-profile sponsors (Home Depot) and one of the highest-profile team owners (former Super Bowl champion coach Joe Gibbs). And, he has quickly become one of the most popular -- and naturally, high-profile -- drivers among fans.

He's also one of the most refreshing, free-speaking, open-minded drivers on the circuit. He says what's on his mind, regardless of the consequences. It's no wonder Stewart is one of the first drivers reporters gravitate to for a quick quote or lengthy comment on the state of NASCAR today.

When new drivers come upon the scene, it usually takes a while for them to literally get up to speed and run with the big names of the sport, like Jeff Gordon, Rusty Wallace or Dale Jarrett.

But when he stepped up to Winston Cup, Stewart started quickly. In his first series event -- the season-opening Daytona 500 -- Stewart qualified on the outside of the front row. From that point on, he enjoyed the most successful rookie season in Winston Cup history, winning three races and two poles. He also had two runner-up efforts and seven other top-five finishes in 34 races. Stewart earned nearly $3.2 million in 1999 and finished an unprecedented fourth in the standings.

	Tony Stewart got the 2001 season off on the right foot by winning the Budweiser Shootout at Daytona.

In his sophomore season, Stewart won six races and two poles, placed second in two other events, and had four other top-five finishes. Despite such strong showings, he slipped a bit in the standings, finishing sixth by season's end.

This season, Stewart has three wins and no poles, plus two runner-up and 10 other top-five finishes. After being knocked out of Monday's rain-delayed Old Dominion 500 after just 40 laps, Stewart fell from third to fifth in the standings behind leaders Gordon, Ricky Rudd, Sterling Marlin and Jarrett.

The road to Winston Cup
Stewart makes no bones about it: the man who inspired him most, and the individual Stewart patterns himself after is racing legend A.J. Foyt. Both men are cut from the same cloth. Both are brash and unafraid to speak their minds. Stewart, like Foyt, also has the raw talent that allows him to drive anything he jumps into with vigor, consistency and, most importantly, success.

Neither Foyt nor Stewart ever failed to succeed in any type of motor-powered vehicle they've driven, be stock cars, Indy cars or sprint and midget rides. Some observers have even gone so far as to jokingly refer to Stewart as Foyt's illegitimate son, they're so much alike in personality and ability.

While he was coming up in the sprint and midget car ranks, Stewart's talent caught the attention of many of racing's biggest names. Indianapolis Motor Speedway President Tony George coveted Stewart to be one of the figureheads of his then-new Indy Racing League. Gibbs wanted Stewart for his Winston Cup team. There were even rumors Roger Penske was eyeing Stewart for a possible seat in one of his CART rides.

As it turned out, Stewart followed the path -- and advice -- of former sprint car rival Gordon to NASCAR. And while he continues to have problems with NASCAR's rules and philosophy, Stewart has found popularity and wealth like he never had on any other circuit. He continues to dabble in other forms of racing, particularly the IRL, including twice pulling off the rare combo of competing in the Indianapolis 500 and Coca-Cola 600 in the same day.

Stewart spoke with ESPN.com about his life in and out of open-wheel racing, as well as the inherent differences between the various forms of racing he's competed in over his career.

Here are some of Stewart's comments:

ESPN.com: How do you assess the differences between open-wheel racing, like midgets and sprint cars, and Busch or Winston Cup-style stock-car racing?

Stewart: "The fact that when you're running a Busch Grand National or Winston Cup car, you're dealing with a 3,400-pound race car. The midgets and the sprint cars we've driven in the past, they're between 900 and 1,200 pound cars. It seems like the heavier the car is, the harder it is to manhandle.

"On top of that, you put radial tires on (stock cars), where in open-wheel cars, we ran bias-ply tires. The bias-ply tires are a lot more forgiving. When you're dealing with 3,400 pounds, the tires aren't as forgiving as far as being able to manhandle the car. Being able to manhandle 3,400 pounds is a hard task by itself."

ESPN.com: There's an old saying in racing that speed, no matter what form of motorsports it is found in, is relative. You drive just as hard, you work set-ups just as much, and you try to dip and dodge the next guy to get to the finish line first, no matter whether you're doing 100 mph or even 225 mph. Is that old adage accurate, or is there a difference?

Stewart: "Sure there's a big difference. With an IRL car, you're dealing with 1,500 or 1,600 pounds, while a Cup car is more than twice that, weight-wise. You have to be very smooth with an IRL car, but you're also able to do things in an Indy car that you couldn't even dream about doing in a Winston Cup car because of the weight and downforce.

"The approaches are different, the mindset that you have to go through is different, about how you have to make adjustments to the car because now you have wings on Indy cars that you can adjust, weight factors that you can adjust, sway bars that you can adjust. Those are things that not only do you either not have, and even if you do have some of them, you can't adjust them in a Winston Cup car.

"The mindset on how to run the race and to make adjustments is a totally different mindset. In the racing and even in practice and qualifying, it's just a lot different way of going about topics, just like in qualifying, what you do in a Winston Cup car to get ready for qualifying, you do totally different than you do in an Indy car series. It definitely adds a whole new set of variables to each equation."

ESPN.com: When you were coming up through the ranks, particularly in the sprint and midget world, was your eventual goal to get to Winston Cup, or perhaps the CART or the then-fledgling IRL series?

Stewart: "I wasn't even trying to be in the CART series, to be honest. I wanted the opportunity to be able to race at Indianapolis, but other than racing at Indy, I really didn't have any expectation about what was going to happen in CART or the IRL.

"I really enjoyed my time in the IRL. I enjoyed the series and its officials. It was a lot of fun to run in that series."

ESPN.com: Twice in the last three years, including this past Memorial Day, you've raced in both the Indianapolis 500 and Coca-Cola 600 on the same day, flying from Indy to Charlotte. Not only that, despite the fatigue and the physical and mental wear that took its toll, you still managed to have outstanding finishes in all four events over those two years. Is it too early to predict if you'll try to do Indy and Charlotte on the same day again next year?

STEWART: "We're looking into it already. If I am going to do it, I'm not going to wait as long as I did this year to make a decision. I'd say it's a possibility. As well as we went through it this year, I'm confident that we can do it next year as easy as we did this year -- and we even had a rain delay in Indy. All things considered, I think it's a reasonable option that we'll do it again next year."

ESPN.com: You're part of a trend of drivers who have gone from open-wheel racing to NASCAR, guys such as John Andretti, Gordon and Dave Blaney. Why is it that, with the exception of Robby Gordon, who has gone back and forth, other drivers don't go the reverse route, say, from NASCAR to the open-wheel worlds of CART, IRL, sprint cars, etc.?

Stewart: "A guy that's in the Winston Cup series now isn't going to go to Indianapolis and try to learn how to drive an Indy car. But there's guys like Robby, myself, and even John Andretti that want to go back to run the Indy 500.

"Those of us that have already been there know how to do it. It's a little bit more realistic of an option. It's just like Michael Waltrip, who runs a Winston Cup race on Sunday, but if there's a Busch Grand National race on Saturday, he'll go and run it because he's used to those types of cars. For anybody in Winston Cup, to put them through all the things they'd have to learn to drive those types of cars to drive an Indy car, it'd be a big challenge for them."

ESPN.com: What was the biggest lesson you learned when you came to Winston Cup racing?

Stewart: "Believe it or not, how to get into and out of the racetrack, find out where the driver meetings were, the other things, the little details. Those are the hardest things to learn. Driving the race car, you still have to learn, but everything else around it, everything that surrounds a weekend of Winston Cup racing, were the hardest things to learn and they're still hard to learn.

"I'm still learning them, like how to deal with the masses of people there, how to budget your time to make sure you're getting plenty of rest while at the same time getting your work done and taking care of the fans. Those are variables that when I got to Winston Cup that I never had in any other series that I was running. There were a lot of things that didn't pertain to driving the car that were probably harder than driving the car itself."

Stewart's history book
The 30-year-old Columbus, Ind., native has been racing since he was a grammar school student. Starting with go-karts, Stewart won the 1983 International Karting Foundation Grand National championship, followed by the 1987 World Karting Association national title.

From there, he went on to make his mark -- which served as a precursor to his eventual entry into Winston Cup -- in the sprint and midget car ranks. He won Rookie of the Year honors in 1991 in the U.S. Auto Club Sprint car series, followed by the 1994 USAC National Midget series championship with five wins in 22 events.

But Stewart was just getting warmed up. He pulled off a feat that still seems incomprehensible even today, being the first driver to win USAC championships in three different divisions in the same year -- Sprint, Midget and Silver Crown, all in the 1995 season.

Stewart left his sprint and midget car roots behind in 1996, jumping to the IRL, where he not only started from the pole and led the first 44 laps at the Indianapolis 500, he also was the Rookie of the Year. The following season, he won the IRL championship.

As if he hadn't conquered enough racing hills already, it was time for Stewart to move on to the next level: NASCAR. While also competing on the IRL circuit, Stewart ran several NASCAR Busch Series races in 1996 and '97, followed by 22 Busch races in 1998, winning two poles and recording five top-5 finishes.

Stewart still remains loyal to his roots, continuing to race occasional dirt track events when his busy schedule allows. He also is owner of a World of Outlaws series team, with driver Danny Lasoski.

Veteran motorsports writer Jerry Bonkowski covers NASCAR for ESPN.com