A brace from on-loan striker Barry Conlon and a superb Nathan Jarman volley sealed a fourth home victory in five for the Mariners.
And Newell said: "We hadn't started well in the last home game against Accrington or at Notts County on Monday but we got the start we wanted in this game.
"Barry's goal was vitally important and then Nathan showed good technique to score his goal and it was virtually sewn up at half-time.
"I couldn't fault the lads at all. Three games in a week can take its toll and maybe that showed near the end but we fully deserved the points."