Which athlete won more MVP awards than any other player in North American professional sports?

There are a variety of North American sports that offer a MVP seasonal award. The most ever for a single sport is Wayne Gretzky who won the MVP award on 9 separate occasions in the NHL. Other notable winners follow:

MLB: Barry Bonds has won the award 7 times in the National League

NBA: Kareem Abdul-Jabbar has won the award 6 times

NFL: Peyton Manning has won the award 4 times

MLS: No player has won the award more than one time