Bobby Rahal, Graham Rahal

Comment on one of Graham Rahal's Instagram posts. He dares you.

"I do all my own social media, for better or for worse," he says with a laugh.

The IndyCar racer tries to read all his Instagram comments. Fans typically commend Rahal on his driving skills, share their love of cars or gush over his relationship with drag racer Courtney Force, whom he wed in November.

Graham Rahal

But one recent taunt jumped out to Rahal.

"Some fan said, 'You never had to work for a thing,'" Rahal recalls. "I say, you have no clue who I am as a person."

Rahal never had a shot to be normal in the racing world. His father, Bobby, won three PPG Indy Car World Series titles and 24 CART open-wheel series races. Most notably, Bobby won the 1986 Indianapolis 500.

As Graham zoomed up the racing world, his father's shadow loomed over him. He won his first IndyCar Series race in his first start at St. Petersburg in 2008 as a 19-year-old. Rahal still had a career ahead of silencing naysayers.

"Fans see my cars and I think they assume that Dad bought them for me or oh, it's Daddy's money," Rahal says. "The truth is my dad bought me my first car and that was it. Every other car I've got. I've gotten to where I am, [financially,] because I'm creative and I like making deals."

In his sixth year on the circuit, in 2013, Rahal made the move to Rahal Letterman Lanigan Racing, the team co-owned by his dad, David Letterman and businessman Mike Lanigan. Graham is now Rahal Letterman Lanigan's premier racer. In 2015, he won two races with eight top-five finishes to finish fourth in the IndyCar Series. In five races in 2016, Rahal has three top-fives.

Of course, he still has the label of being Bobby's son. It will take years to surpass his father's accomplishments. A good place to start would be to win Sunday's Indy 500, 30 years after his father's lone title. Graham did his studying earlier this month.

Bobby Rahal, Graham Rahal

"The other day, I was working out and I was like I'm just going to turn on '86," says Rahal, who commonly watches race tapes in the gym. "I'd seen it before, but I watched the last 40 laps. Seeing the way he won the race, on a restart, and then just took off, it was such a methodical approach. That's who he is if you know my dad. That moment is what changed our family name forever, more than anything else he's accomplished."

As much as Rahal tries to be his own person, he admits much of his characteristics run parallel with his father. "Probably 95 percent of life, I'd just kind of follow his lead and learn from him," he says.

But that other five percent?

"I'm probably more aggressive than he is, which is amazing, because when I was a kid, I thought he was the most impatient person I knew," Rahal says. "Now, I think he was more patient than I am. On the race track, I'm a pretty aggressive guy, I like to attack and sometimes bang wheels with some guys. Dad was never that guy. He kind of kept his distance, kept it smart, kept it clean."

When Graham was born in 1989, Bobby was already established. The family's livelihood and fame were based off Bobby's finishes. Graham grew up in the Columbus area, in the heart of IndyCar country. He hung around Bobby's famous friends, like Letterman, whom Bobby met in the early 1980s.

Graham Rahal Car

Now their success is based on Graham's performance. Bobby can organize the team as much as he can, but once the race starts, it's up to Graham's driving.

"My boss to me is Mike Lanigan because I think Mike has a bigger influence on the day-to-day finances," Graham says. "Nothing gets done without Mike's approval. Sure, I work for my dad, but at the same time, my dad works for me in the sense that he's out there selling sponsorship, he's busting his butt to put together a good team to give me the tools to being successful. It comes down to being a partnership."

That's a professional statement from a 27-year-old, who carries himself more like a 40-year-old veteran. The good news for Rahal is the third team owner can give him some comic relief. Letterman, an Indianapolis native, retired from The Late Show about a year ago and has more time to pop in on Rahal's races.

David Letterman, Graham Rahal, Courtney Force, Bobby Rahal

"It's funny, since he retired, when I talked to him at Long Beach, it sounds like he's just as busy as he was before, keeping himself occupied," Rahal says. "For him, it's all about trying to enjoy family time with Harry and Regina and the rest of the fam. He's got his place in Montana, I don't know if he's there. Who knows where he's at?

"He makes a lot of jokes. He normally makes fun of my other boss, Mike. He loves to make fun of him. He's pretty hard on Lanigan. He's a funny guy. The thing about Dave is it's such a dry sense of twisted humor, it's like his show. Some people don't catch on, others, it takes a second, but he's extremely creative and funny."

According to Rahal, Letterman will be in Indianapolis this weekend. (Tune in to check out the length of his beard.) Letterman is partly responsible for Rahal's primary sponsorship of Steak 'n Shake. His love of steakburgers and milkshakes fuels Rahal's car.

Graham Rahal, David Letterman

"The Ed Sullivan Theatre's got a Steak 'n Shake right there," Rahal says of the Indianapolis-based chain. "Back in the day, when Dave lived in Indy, when he went to high school, the bus stop for the Indy Motor Speedway dropped you off right in front of the Shake 'n Shake. That's how he became a fan.

"It's something I believe in and it's something fans embrace. There's other products you try to sell that fans just don't take to ... People probably think, 'Oh, he's a Rahal, he probably sits at home and gets a paycheck from Dad.' I'm a business. I'm a hired driver. I keep track of my appearances. When we go over, I get paid."

Rahal has his own shake, which is a simple chocolate with M&Ms. Last August, for every fan who bought the shake in Ohio, $1 was donated to Nationwide Children's Hospital for SMA research.

Rahal's partnership with Steak 'n Shake also aligned with a sweet turning point in his career. After winning that first race in 2008, Rahal did not have a second IndyCar Series victory through 2014.

"I never thought I don't want to do this, but I thought if this is what this is, I'm not having fun," Rahal reminisces. "We cleaned house in the fall of 2014 and all of a sudden, boom, it ticked. It was a major lesson for me in life and I think for everybody that was a part of my team. Ever since, we've had a heck of a lot of fun."

Graham Rahal, Steakn 'n Shake

Rahal's career got back in the right lane, and his expectations are still through the roof. Despite his early struggles, Rahal is well ahead of schedule.

"I need to win championships and I need to win an Indy 500 or two, and I feel like I have a good chance at it," he says. "I'm 27 now and most guys hit their prime in their early 30s."

Above all, looms that big race on Sunday.

"If I couldn't win a couple championships, at least I'd win a 500 or two," he says. "I don't want to say winning championships isn't important, but ultimately winning the 500's more important than winning a championship. That's the truth."

Like father, like son, to a point. Rahal is branding himself as an individual, on and off the road.

If he crosses the finish line first on Sunday, his name will be etched in Indy 500 glory right alongside his father's -- which is actually what Graham Rahal needs for his own legacy.

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Follow Jeffrey Eisenband on Twitter @JeffEisenband.