Some of the biggest excitement for fans comes from picking their brackets and seeing if they've got the winners.
A KELOLAND company is behind several national websites on bracket madness.
It started with a local fantasy gaming site called Sports Geek, when the digital marketing firm, 44 Interactive's work got noticed on the national playing field.
"Then it got picked up by some guys that left EA Sports in California that liked what we'd done. They hired us to build their solution called Daily Joust,” Wade Humphreys of 44 Interactive said.
The Daily Joust is now the third most played fantasy sports betting site in the world. Fantasy Sports gambling online is legal because it's considered a game of skill, not chance.
"So we've really been exposed to fantasy gaming sites for quite some time; really deep down in the trenches of coding and understanding the concepts behind these sites. It's a huge multimillion dollar industry today with a lot of fanfare. We took all that exposure and experience and built our own called Pick Envy," Humphreys said.
Pick Envy has taken in as much as a million dollars a day in wagers. That success got 44 Interactive noticed by a national chain, the pub The Tilted Kilt who asked the company to design its March Hoops Bracket Challenge site.
And that is likely to attract even more attention to this little South Dakota company.
"You do get a little bit of flack from partners outside the state about being from South Dakota. But when they see the work and the service you do---the beauty of the web is you don't need to be in the same town as your customer. You're able to provide the services, globally even," Humphreys said.
And it's still not too late to get your brackets filled in on one of the 44 Interactive designed websites.