That is debatable. Michigan has had the most fans in a stadium in a game, and there are fans growing everyday.
Michigan
notre dame
oklahoma
Ohio State
LSU
Michigan State Spartans
Florida Gators from the University of Florida
The University of Michigan Wolverines have 25 undefeated seasons.
Texas
The University of Alabama and the University of Oklahoma are tied for the most with 30 ten-win seasons. This is including the 2009 season.
30 - Florida State