Klein confirmed the news on his Twitter account:
He had a very decorated career at Kansas State. It wasn't until his junior year that Klein really caught on as a Wildcat. In 2011 and 2012, he combined to throw for 4,559 yards and 29 touchdowns. Even more impressively, he rushed for 2,061 yards and 50 touchdowns.
In his senior season, he finished third behind Johnny Manziel and Manti Te'o in the Heisman Trophy voting. Klein did earn himself the Big 12 Offensive Player of the Year Award.
He helped to spark what was a Wildcat revival under legendary coach Bill Snyder. Kansas State finished 10-3 with a loss in the Cotton Bowl in 2011 and 11-2 in 2012, losing to the Oregon Ducks in the Fiesta Bowl.
Despite his success, it wasn't a huge surprise to see him go undrafted. Although this draft class was generally much weaker than what fans have seen in years past, Klein doesn't have the kind of skill set teams are looking.
Klein is not your prototypical NFL quarterback. He's not a great passer, nor is he athletic enough to overcome his failings in the passing game.
Going to a team like Houston is perfect for somebody like Klein. Matt Schaub is already the established starter. There’s no threat of Klein needing to be thrown into the NFL anytime soon. He can sit on the bench and learn from a talented QB like Schaub.