To answer this question requires a little history lesson. Until 1972 the game was actually blacked out in the host city. The broadcast was not truly nation wide until 1972. So what was the first commercial that caused people to talk after the game and really affected product sales?

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The first Super Bowl was played between the NFL champion (the original professional football league) and the upstart AFL (American Football League.)  That was 1967 and the Green Bay Packers won the first two Super Bowls as the NFL representative. In Super Bowl III a cocky AFL quarterback named Joe Namath guaranteed an AFL victory for which he was heavily ridiculed. He was featured in a commercial that played during the game for Noxema Shave Cream. His prediction held true and his New York Jets won the game. Winning the game did not hurt Noxema sales and made people talk about the commercial. The power of commercials in the Super Bowl was discovered and advertisers never looked back. Now you know where it all got started. You might notice that his hair style has came back!