The Dude

According to Wikipedia, rematches in conference championship games are 23-14 in favor of the first game winner.  I am actually surprised it has happened that often.  In bowl games, the losers are 15-7 in rematches.

https://en.wikipedia.org/wiki/List_of_college_football_post-season_games_that_were_rematches_of_regular_season_games

I don't put much stock in the beating a team twice thing.  NW could win because they are annoying sidlers.  They just don't go away and at the end of the game, there they are with a chance to win.

Northwestern wins more games from other teams losing rather than them winning.