In the run-up to the World Cup, genetics company 23andMe looked to capitalize on the scramble of soccer fans in the United States, searching for an alternative team to support. Most fans of the game here in the States have long formed bonds with second and third teams from around the world. While some fans here in the states have links to Latin American sides, many hyphenated Americans or those with just a loose sense of their ancestry have long supported old world teams like Italy, Spain, Germany, or Poland.
This is anecdotal of course, and plenty of soccer fans here support popular teams like Brazil and Argentina due to their historic talent or England due to the commercial success of the EPL in the States.