Tournament Challenge: 1 perfect bracket

Through 24 games, there is just one perfect bracket (out of 8.15 million) entered in ESPN.com's Tournament Challenge. The number of perfect brackets had been reduced to two with La Salle's upset win against Kansas State, and the Illinois-Colorado game broke that deadlock at the top.

The one perfect entry is not listed on the leaderboard on ESPN.com or the Bracket Bound app because it is not eligible to win a prize on ESPN.com. That entry has a Final Four of Louisville, Georgetown, Ohio State, and Syracuse, with Louisville beating Georgetown for the title.

President Obama is currently 14-10/15-9 through the first 24 games, landing him in the 37.2th percentile. He lost an Elite Eight team in Wisconsin, but he did pick La Salle's upset of Kansas State. There are 80 brackets to get 23 of 24 correct.

Notes from today's upsets:

-- Just 6.1 percent picked 13-seed La Salle over 14-seed Kansas State. It was the second-biggest upset so far (according to our user picks) in the tournament. About 5.6 percent of brackets correctly picked Harvard over New Mexico State on Thursday.

-- Only 20 percent of brackets had 12-seed Ole Miss beating 5-seed Wisconsin. The Badgers were a popular bracket pick, selected to reach the Sweet 16 in 54.7 percent of brackets and the Final Four in 9 percent of brackets. Plus, President Obama had Wisconsin reaching the Elite Eight. And 3.7 percent of brackets correctly picked the 12-seeds of Ole Miss, Oregon and Cal winning its Round of 64 games.

-- 30.4 percent of brackets picked 9-seed Temple to beat 8-seed NC State. The Owls were the least popular of the 9-seeds to advance.

-- 2.7 percent of brackets picked both Philadelphia schools (La Salle, Temple) to win in this round. And looking ahead to tonight, 1.5 percent of brackets picked the trio of La Salle, Temple and Villanova to win.