Can World Cup mania grow MLS in the U.S.?

As the World Cup comes to a close, so does a massive real-time experiment happening just around the edges. Major League Soccer – the top men’s professional soccer league in the U.S. and Canada – has been scrambling to take advantage of this once-in-a-generation opportunity when average American sports fans suddenly cared a lot about soccer. In between World Cup matches, NPR Sports Correspondent…