The Seattle Sounders FC took Major League Soccer by storm in its inaugural season of 2009. The club led the league in attendance, won the Lamar Hunt U.S. Open Cup trophy, and clinched a playoff berth. The team’s success was attributed in part to its rabid fan base, which routinely sold out its 30,000-seat venue and nearly doubled the league attendance average. How was it that an expansion franchise was able to garner such immediate, fervent support, while original franchises with well-established fan bases struggled? This case study sought to supplement the limited current literature regarding the motivating factors of American soccer fans. Through a survey of first- and second- year season ticket purchasers and the use of SEM analysis, the relationships among sport attachment, attachment to community, the need for vicarious achievement, team identification, and fan superiority were examined. Results indicated that although similar across most relationships, sport attachment predicted team identification in those individuals who bought season tickets for the first time in the second year of the team’s existence, whereas there was no significant relationship between those two variables in those fans who bought during the first year.