Soccer is the most popular sport in the world. So it would be logic that soccer would have the most fans.
As of 2014, the professional sport that has the most female fans is NASCAR. NASCAR is a stock car racing series.
That would be American Football.
Many sports fans are passionate about their sport and their favourite team. So there is no real answer to this question. Traditionally football fans sing at most grounds and support their team for the length of their lives. Football teams around the world have an attachment to the area and cannot be moved. However cricket fans in India are passionate, in usa gridiron and baseball fans are noisy and care for their favourite team, as do ice hockey fans in Canada. So no one sport has all the most passionate fans. Football has the most fans around the world and thus the highets number of passionate fans so if that is what you were asking, which sport has the largest number of passionate fans, then the answer would be football.
Baseball, it's the national pastime.
The passionate fan is the Seattle Seahawks
Probably American football or basketball.
The sport that has the most fans is without a doubt, hockey. hockey is the most widely played sport in the world. Just about every country has a hockey team, and other than the U.S., most countries take hockey very seriously. Countries like Brazil, Italy, and Germany are huge hockey fanatics and have thousands and thousands of fans watching.
football or soccer with trillions of fans world wide.
The most popular sport for men is football. Football was invented by the Chinese and in the last century has had the most male fans in the world!!!!!