Patrick is a huge attraction since she earned 2005 rookie of the year in the series. She became the first woman to win an IndyCar race in 2008, and last year she had a career-best, fifth-place finish in the drivers' standings. She also came in third at the Indy 500, the highest finish by a woman.
Before Patrick, there were a few women making their way to IndyCar racing.
Janet Guthrie became the first woman driver at the Indy 500 in 1977, and she was followed by Lyn St. James in 1992. But it wasn't until 2000 that a 19-year-old Fisher got to Indy.
Fisher was the first to run a full IndyCar season in 2001, and the first to win a pole in a major open-wheel circuit in Kentucky in 2002. She was the most popular driver from 2001-03, but failed to secure enough sponsorship to regularly race in the series. She created her own team in 2008, Sarah Fisher Racing.
The 37-year-old Duno, the series' first Hispanic female driver, will be making her 27th IndyCar start on Sunday. For the first time, she has a seat for the entire season. Duno, who has four master's degrees, hasn't had significant results in the series so far.
Simona De Silvestro is coming from the Atlantic Series, where the 21-year-old driver became the second woman to win a race in the developmental series in 2008. She won four times last season and just missed the title after retiring in the final race.
Terry Angstadt, president of the series' commercial division, says having women in the mix is good for business.
"It's just great to have these women in our sport," Angstadt said. "It's good for the business. Racing is the only sport where female athletes compete in absolutely the same field as the men, they race on exactly the same tracks, the same cars."