According to Forbes, "Our ranking is based on five criteria: hometown crowd reach (defined by Nielsen Scarborough as a percentage of the metropolitan area population that watched, attended and/or listened to a game in the last year), three years' worth of television ratings (per Nielsen), three years' of stadium attendance based on capacity reached, three years' worth of merchandise sales (per NFLShop.com), and social media reach (a combination of Facebook likes and Twitter followers based on the team’s metro area population).
Based on that criteria, the team with the best fans: the Green Bay Packers. Packers fans finished first in all categories except TV rankings (2nd) and merchandise sales (7th).
The full list:
1. Green Bay Packers
5. Baltimore Ravens
10. Chicago Bears