The next two years , the Raiders again won Western Division titles , only to lose the AFL Championship to the eventual Super Bowl winnersâ '' the New York Jets ( 1968 ) and Kansas City Chiefs ( 1969 ) . The following two years , the Raiders again won Western Division titles , only to lose the AFL Championship to the eventual Super Bowl winnersâ '' the New York Jets ( 1968 ) and Kansas City Chiefs ( 1969 ) .