Sixteen years ago, before UCF even joined a conference or played in it's first bowl game, UCF drew over 50,000 to the Citrus Bowl in a game vs Virginia Tech. Considering the opponent, there is no way Virginia Tech had more than 5,000 fans at the game, meaning the vast majority were there in support of UCF.
Compare that to the (at the time undefeated) Bulls, who are picked to win the AAC east this year. They had a Top 20 in-state team (2nd most popular team in Florida) visiting and filling anywhere from 18,000 - 25,000 seats, and still only drew 52,000.
That should forever end the debate on which school has the most support.