Tournament Challenge: Let it begin

Tournament Challenge opened for business around 7 p.m. ET and in the first three and a half hours, there were around 630,000 brackets already filled out.

Kentucky is the most popular pick to win it all so far, being named the champ on 32.1 percent of brackets, followed by North Carolina (15 percent) and Syracuse (11.2 percent). Interestingly, Missouri, a No. 2 seed, is fourth on the list at 7.7 percent, ahead of Michigan State (6.7 percent), the No. 1 seed in Mizzou's bracket.

The top 10 teams to win it all:

Kentucky: 32.1 percent

North Carolina: 15 percent

Syracuse: 11.2 percent

Missouri: 7.7 percent

Michigan State: 6.7 percent

Kansas: 5.8 percent

Ohio State: 4.1 percent

Duke: 3.9 percent

Florida State: 2.8 percent

Baylor: 1.5 percent

Kentucky (65.5 percent) and North Carolina (52.9 percent) are the only teams to reach the Final Four in more than 50 percent of brackets. Also, 18.3 percent of entries have Kentucky and North Carolina meeting in the championship game; 12 percent have a Kentucky-Syracuse final.

Among notable early returns from the Round of 64 predictions:

  • Two double-digit seeds (No. 11 NC State, 51.9 percent; No. 10 West Virginia, 51.4 percent) were picked to win by more than 50 percent of brackets. UConn (69.5 percent) is the only 9-seed picked to win by more than half the brackets.

  • The most popular 12-seed to pull off the upset is VCU at 36.9 percent.

  • Belmont, a 14-seed, is picked by 13 percent of brackets to pull off the first-round upset over Georgetown, more than any of the other 13 seeds.

  • The most popular 8-seed to win the first round is Kansas State at 77.8 percent.