NASCAR and IndyCar are the pillars of motorsport in the United States. The two series often act as competitors in the racing realm but require drivers to employ different skills due to the differing nature of the cars.
Despite this, few drivers have been able to get on top of the demands of the two series and have won at least one race in both the championships. Let's look at five drivers who have won a race in both IndyCar and NASCAR.
#5 Tony Stewart
Tony Stewart is known for his work in the NASCAR realm as he has won four championships in the top class of stock car racing (one explicitly as an owner) and claimed 49 wins in the Cup Series. While his racing in the 21st century has been in the world of stock car racing, Stewart had a distant connection with the open-wheel racing scene.

The 53-year-old is the only driver ever to have won both NASCAR and IndyCar championships. He won his open-wheel racing crown in 1997 and has three wins in his trophy cabinet.
#4 A. J. Allmendinger
A. J. Allmendinger often finds his way onto the NASCAR Cup Series grid every once in a while. He has won three races in the premier class of stock car racing but has 18 victories in the Xfinity Series.
On the other hand, he has five victories in the top class of open-wheel racing in the United States. All of his victories came in the 2006 Champ Car season, where he went on to finish third in the drivers' standings.
#3 A. J. Foyt
The legendary IndyCar driver has earned motorsport crowns worldwide. He has won the most races in the series by any driver, as he has amassed 67 wins in his career spanning almost four decades in the open-wheel racing scene.
The 90-year-old also used to race in the NASCAR Cup Series. He took part in 128 races and won seven of them. Foyt's last victory came at the 1972 race in Ontario, when he was 37.
#2 Juan Pablo Montoya
Juan Pablo Montoya has had varied success in the racing realm. He has won the elusive 24 Hours of Daytona, while he has the expertise of racing in both IndyCar and F1.

The Colombian claimed his only IndyCar championship in 1999 and has 15 victories in the series. His latest open-wheel win came at the 2016 St. Petersburg Grand Prix, while he has two wins on the NASCAR Cup Series front.
#1 Mario Andretti
Mario Andretti laid the foundation of the Andretti racing giant. He has won both F1 and IndyCar titles in his expansive racing career.

The 85-year-old has 52 wins in open-wheel racing in the United States and a solitary victory in the Cup Series, which he achieved at the classic 1967 Daytona 500.