I lived 10 years in Colorado (the entire 1990's) and couldn't stand the Broncos. There were good fans there, but many of them were simply fair-weathered fans.
Following Colorado, I lived in Washington State for 5 years, where the Seahawks were "meh". No one at all seemed to care about them.
I've now lived in New Zealand for over 13 years, where the All Blacks rugby team are everything.
I know it's not "American Football" or "Gridiron" as we call it here, but I gotta say that I love the All Blacks.
(They're my only team that has ever given me a championship.)
Let's go AB's!