Ryan Cresswell broke the deadlock in a tight game, just after the hour mark as the Cobblers finally wore down their relegation-threatened opponents.
4,428 watched a game that leaves Northampton just three points away from a play-off place with another home fixture to come against a struggling side, Carlisle United, this midweek.
New loan signing James Gray started the game while recent arrival Ross Perry watched from the substitutes' bench.
More to come on Cobblers Mad.