'Championship 4' battle in 'The Tonight Show 500' relay race

Before heading to Homestead-Miami Speedway for the final race of the season, the "Championship 4" drivers squared off in New York City's Rockefeller Plaza for "The Tonight Show 500."

Jeff Gordon, Kyle Busch, Kevin Harvick and Martin Truex Jr. were each paired with a partner for the relay race: Gordon with host Jimmy Fallon, Busch with The Roots' Tariq, Harvick with teen heartthrob Justin Bieber and Truex with actor Jesse Tyler Ferguson.

There was also plenty of tweeting.