After Week 12, only Clemson and Iowa are still undefeated.

When the first College Football Playoff top 25 was released on Nov. 3, 11 undefeated teams dominated the rankings. Just a few weeks later, only two undefeated teams remain — Iowa and Clemson — after three more fell on Saturday.

Source: After Week 12, only Clemson and Iowa are still undefeated.