If The Victors and Across the Field are more recognized tunes, I wonder if listeners are as likely to associate them with their schools as they'd be with On Wisconsin.
I would say 'The Victors' is easily the most recognized fight song in the Big Ten and along with the Notre Dame's 'Victory March', the two tunes most associated with their school in the country.
No disrespect to 'On Wisconsin', but it would finish a decent distance behind those two with the distinct possibility of several songs in between (possibly USC March On, Tennesse Rocky Top, Oklahoma Boomer Sooner, The Eyes of Texas, and others). Of course, all personal opinion, I understand.