After losing the opening match of the final CONCACAF qualifying stage to Honduras, Jurgen Klinsmann's side bounced back with a hard-fought triumph at a snow-swept Dick's Sporting Goods Park in Colorado.
The only goal arrived on 16 minutes as the Tottenham ace swept the ball home to take USA into second.
They are still a point behind Honduras, who came from two goals down to seal a draw with Mexico in San Pedro Sula.
Manchester United star Hernandez scored either side of the break, but Honduras battled back thanks to goals from Carlo Costly and Jerry Bengtson.
Jamaica and Panama are both on two points after two games after playing out a 1-1 draw in Kingston. Bristol City's Marvin Elliott put Jamaica ahead but the visitors sealed a point courtesy of Luis Henriquez's strike.