300 million people live in USA.
3 million kids between 5-19 years old play soccer.
Considering that's only children who play soccer and not anyone who just likes, then it must be around 30%
The national team in the last few years (Getting into the 2006 and 2010 World cup) has made more people aware of soccer. Also players like David Beckham playing in the MLS has made more people aware of the sport.
It's more than you think
The odds that the US soccer team would win the 2014 World Cup is about 23 percent.
The percent is something like 73.1 %
more than 50 percent its the most popular sport in the world
Soccer in Europe is generally thought to be played at a quicker pace than US soccer
Soccer is U.S.
there is the women's us soccer team.
Soccer is played somewhere in the US every day.