While the National Football League remains the most popular professional sports league in the United States, a new SportZ study by WPP suggests that NASCAR is closing the gap. According to the study, 41 percent of sports fans agree that NASCAR is becoming more popular and 38 percent saying it is attracting new types of fans and 37 percent say there is a definite buzz or excitement about the sport.

Among those surveyed, 57 percent believe that NFL football is exciting to watch, but attitudes about the sport as a business are slightly negative, with 48 percent agreeing that the league is more interested in making money than entertainment, and another 46 percent claiming the sport is costing too much for fans to follow.

The SportZ research also studied the nature and behavior of each sport’s target audience, finding that 40 percent of NASCAR fans are female as opposed to 32 percent of NFL fans—a significant gap considering that women determine how 88 percent or every disposable dollar is spent. And while both NFL Football and NASCAR fans use the internet, almost one-third of female NASCAR fans have not done so in the past 30 days.

WPP’s SportZ is backed by WPP companies Hill & Knowlton and Premiere Sports Group and is carried out by Millward Brown.