The late surge allowed a sellout crowd of 50,007 to relax, assured that Kansas State wouldn't need more late-game antics in an opener against a middling opponent.
The Wildcats needed a long touchdown pass from Klein in the waning minutes to beat Eastern Kentucky, another program from the Football Championship Subdivision, last season.
Missouri transfer Ashton Glaser was 22 of 44 for 257 yards for the Bears (0-1), who won just two games last season and had been going through some turmoil. Special teams coach Bob Montgomery resigned just 10 days ago so to pursue a business opportunity.
It was the 20th consecutive season-opening win for Kansas State coach Bill Snyder, who returned to the sideline four years ago after a brief retirement to rescue a program that had fallen back on hard times. The Wildcats won 10 games and reached the Cotton Bowl last season.
Expectations are much higher this season the Wildcats no longer will sneak up on anybody and that showed when Missouri State gave everything it had most of the night.
The Bears had a healthy advantage in total offense by the end of the third quarter but were done in by a couple mistakes that kept points off the board.
Wide receiver Julian Burton fumbled just short of the goal line to waste a touchdown chance in the first quarter, and a dropped pass midway through the fourth wiped out another likely score.
The Wildcats certainly didn't give the Hurricanes, who beat Boston College earlier in the day, any helpful video to prepare for next week's matchup in Manhattan, Kan.
They hardly blitzed on defense and ran a vanilla offense, and that was part of the reason the game was close into the second half. Klein didn't take off on a designed run until midway through the second quarter after carrying 317 times last season. He finished with just 54 yards rushing.