Nicola Rigoni's smart finish gave the visitors an early lead before Argentine forward Gonzalo Higuain levelled with his 26th Serie A goal of the season.
Goals by former Tottenham defender Vlad Chiriches and Jose Callejon sealed the points.
Juventus will go three points clear at the top if they win away to Atalanta on Sunday.
Elsewhere in Serie A, Sampdoria moved eight points clear of the relegation zone by defeating bottom club Hellas Verona 3-0.
Verona are nine points from safety with 10 games remaining.
Napoli returned to the top of Serie A on goal difference from Juventus after coming from behind to defeat Chievo.