As usual, there will be few if any unbeaten at the end of the year.
13 teams in the Top 25 are unbeaten right now, Make it 14 if you count Arizona moving into the rankings. By conference:
SEC - 5 (Bama, Auburn, TAMU, Ole Miss, Miss State)
Big 12 - 3 (OK, Baylor, TCU)
Pac 12 - 2 (UCLA, Arizona)
Independent - 2 (ND, BYU)
ACC - 1 (FSU)
B1G - 1 (Nebraska)
Only one unbeaten can come out of each conference plus NDvsFSU so we are left with only possible unbeaten of:
SEC
B1G
Big 12
Pac12
ND/FSU
BYU
UCLA/Arizona I think are least likely to produce an unbeaten. With Stanford and USC on both schedules plus Oregon yet on UCLA's schedule I don't think either team is anywhere close to good enough to beat all the above and probably Oregon a second time in a championship.
Close second, Nebraska surviving the B1G unbeaten. Probably will fall this weekend AT Mich State but also have to go to Wisconsin and win on top of a B1G championship game. Overall schedule is not that imposing but winning AT their two toughest opponents I don't think is happening.
Next is the SEC, I have a hard time seeing any of those teams run the gauntlet. TAMU, ole Miss and Miss St are all overrated so might make it look tougher than it is for Bama and Auburn but they also have LSU and the East champ to contend with. I won't be at all surprised if we have a two loss SEC champ enter the playoffs. Pretty low chance of unbeaten IMO.
Big 12 really comes down to Oklahoma and Baylor. TCU gets their shot at home against OK this weekend. Then Baylor and OK play in November. Easy to see the winner going undefeated, especially since they don't have a conference championship.
FSU/ND - If we don't beat them who will? Probably nobody. If we do win (and come into the game undefeated) we look pretty good coming off our toughest three game stretch. We have to beat Stanford first though.
BYU might have the easiest path to zero losses. If there are no other unbeaten teams that makes it really hard to exclude them. It also makes it harder to let a one loss ND into the mix and pinch two conference champs.
At the end of the day. Pretty good odds that nobody is undefeated, which completely changes the dynamic of this conversation.