I used Massey Computer ratings (
http://www.mratings.com)
to compile the probability of each undefeated college football team remaining undefeated at the end of the regular season. Here are the probabilities:
Oklahoma 47.48 %
LSU 16.77
Nebraska 14.6
N Illinois 11.79
FSU 13.18
Minnesota 10.61
Arkansas 10.13
Miami 10.11
VTech 5.73
OSU 3.81
Using these, the probabilty of at least one team finishing the regular season undefeated (pre-league chamionships and bowl games) is: 81.2%