By the 1960s, the sportscar race was made into a 24 hour race. This required multiple drivers for each car and involved a long period of racing at night. Both races grew in popularity in the 1970s and 80s. Today the Daytona 500 is an important race in NASCAR. The Rolex 24, which is named that because it is sponsored by the Rolex watch company, is an important endurance race.