It depends somewhat on success. Tennessee came in between 13 to 15 in past years but was 5th last year when they finally had a good year again. If these teams win, their following rises dramatically. SEC has the big 6 of Alabama, Auburn, Florida, Georgia, LSU, and Tennessee. Kentucky is great in Basketball. Of the expansion teams, you can consider Oklahoma, Texas, and A&M among that group now. The two Texas teams make the most $ based on most rankings. I do think Ohio State has the biggest fanbase of any program, however. Notre Dame has a very large following as well but it is slipped over time because they haven't been a true contender since the 1980s.