Don't have Insider, but someone over at Phog posted the top 2 teams.
Most Tourney Wins since 2000
Two-way tie atop 21st century NCAA tournament leaderboard
In the 17 tournaments so far this century, 150 Division I programs have tasted victory in the Big Dance at least once. In fact, six new teams joined that club just in the 2016 tournament. Congratulations to Arkansas-Little Rock, Hawaii, Holy Cross, Middle Tennessee, Providence and Yale.
At the other end of this spectrum there are, well, the usual suspects. Certainly the easiest measure of tournament success is how many titles you win. By this yardstick, Duke and Connecticut are tied with three championships apiece this century, though Huskies'fans will be quick to remind you their team has actually cut down the nets four times since 1999. (And, yes, UCLA fans might point out their team has won 11 titles in total.)
Then again, tournament games won this century can give us an additional and even more fine-grained picture of which programs have been consistently successful over the past 15-plus years. With that in mind, here's an updated list of the most successful tournament teams of the century based on victories since 2000. When applicable, ties were broken according to number of national titles:
1. Duke Blue Devils (42 wins)
National titles: 2001, 2010, 2015
The last time we did this list, Duke was in a first-place tie with Michigan State. Now the Blue Devils sit atop this list alongside Kansas. That being said, the Jayhawks, Spartans and every other team might need to step up their game to keep up with coach Mike Krzyzewski, who has what appears to be a pretty strong team ready to go next season. It's possible Duke could be adding four, five or even six tournament wins to its total for the century in short order.
2. Kansas Jayhawks (42 wins)
National title: 2008
Michigan State had its Middle Tennessee episode; Duke's ghosts wear uniforms from Lehigh and Mercer; and North Carolina missed the tournament entirely as recently as 2010. But the last time Kansas failed to win at least one game was the 2006 tournament. No team in the country can match Bill Self's 10-tournament-and-counting streak in this respect. Gonzaga, with wins in eight consecutive tournaments, comes closest.