quick and easy way is this....
have each entrant fill out their projected winner for each game of each round through the championship...
For each correct winner, award 1 point for each correct first round winner, 3 points for each second round winner, 6 points for each third round winner, 9 points for each fourth round winner, 12 points for the fifth and 15 points for the national champion.
As a tiebreaker, have each entrant include their projected total score for the championship game.
person with highest number of points wins....you may want to provide that 70% of the money goes to the winner, 20% for second place and 10% for third..or something like that.