How many teams in college football history have played in a national title game with 1 loss?

Answer 1

First of all, I'm limiting my answer to Division 1-A, since a) that's probably what you were really asking about, b) that's all anyone cares about, c) that's all I know, and d) the list would be very, very long if you included all divisions.

For Division 1-A, there was no such thing as a "national title game" until the 1998 season, and even then it was not, and still is not, sanctioned by the NCAA. It is called the "BCS National Championship Game". The 9 teams that have played in that game with one loss are listed below.

Florida State Seminoles (1998, Lost National Championship Game)

Florida State Seminoles (2000, Lost)

Nebraska Cornhuskers (2001, Lost)

LSU Tigers (2003, Won)

Oklahoma Sooners (2003, Lost)

Florida Gators (2006, Won)

Ohio State Buckeyes (2007, Lost)

Florida Gators (2008, Won)

Oklahoma Sooners (2008, Lost)

Twice (2003 and 2008), both teams in the national championship game had 1 loss going into the game. Of the 12 BCS National Championship Games played so far (1998-2009 seasons), 7 have had at least one team with 1 loss.

Also, if you're interested, the 2007 LSU Tigers played in the national championship game with two losses (both in triple overtime), and beat Ohio State to win the national championship. So, there are 10 teams with "at least one loss" that have played in the National Championship Game. (And there are three times when both teams had at least one loss.)