Here are some key Tournament Challenge stats on the Final Four.

1. Out of 4.78 million brackets on ESPN.com, 200 successfully picked the correct Final Four.

2. 304,924 brackets (6.4%) picked Duke to win it all.
224,417 brackets (4.7%) picked West Virginia to win it all.
28,379 brackets (0.59%) picked Michigan State to win it all.
4,568 brackets (0.1%) picked Butler to win it all.

3. 10,212 brackets picked a Duke/MSU championship game.
6,951 brackets picked a WVU/MSU championship game.
1,430 brackets picked a Duke/Butler championship game.
1,664 brackets picked a WVU/Butler championship game.

4. After failing to select any of the Final Four teams, President Obama has fallen all the way to the 55.8 percentile, ranked 2,111,104, and will drop further after next Saturday and Monday's games.

Celebrity brackets below:

President Obama
LeBron James
Dick Vitale
Mike Greenberg
Mike Golic
Joe Lunardi
Bill Simmons
Michael Wilbon
Colin Cowherd
Michelle Beadle
Scott Van Pelt
Doug Gottlieb