I don't know how else you would come up w/ such statistics. Also, click on the "current league voting statistics" and then click on "list by popularity". According to this, we have the 6th most fans nationwide. Again, it may be the result of jimmering the poll...but if you look into the methodology, they try to block that from happening. I think what this does show is that BYU has a national following, vice just a state or regional following.
http://commoncensus.org/sports_map.php?sport=5