Here is a college football
map of fans from the NYT.
A few takeaways:
Texas is the leader in almost the entire state of Texas with only small exceptions right around the campuses of aTm, Baylor, TCU, and UTEP.
Nebraska is a lot more valuable than they would be based solely on state population because they are the primary team in not only all of NE but also NW MO, Northern Kansas, NE CO, all of SE, SW MN, and Western IA.
Oregon may be more valuable than we think because they not only dominate Oregon but also have substantial fanbase spill-over in WA, CA, AK, and MT.
Ohio State's value comes from being the ONLY major program in the state. The Buckeyes are one of the very few schools to be the #1 team in every single zipcode in their home state. Also, Ohio is the most populous state to have one lead team in the entire state. Others such as Nebraska are MUCH less populous. They also have some bleed-over in PA, WV, KY, IN, and even MI.
Granted this is from 2014 but at least then USCe dominated most of SC with Clemson only being the #1 team in a small area around their campus.
Iowa dominates their state with ISU only being primary in a few zipcodes around their campus.
Kansas is the main team in most of their state but not all. Nebraska is #1 in the North, Oklahoma is #1 in the South, and KSU has a few zipcodes around their campus.
Indiana is a convoluted mess. It looks like at least 7 schools are #1 in at least some IN zipcodes (IU, PU, ND, IL, Louisville, tOSU, KY).
Syracuse may be more valuable than we think. They appear to dominate upstate NY and have a strong presence in the City. Within the City itself lead teams include Cuse, ND, PSU, RU, and MI but the "lead" team is usually only around 10% of the fans.