Colchester made it seven wins from nine at home and six from their last eight in all competitions, as they moved into the top three for the first time this season.
It was not a free flowing game but, for the second week running, the U's made sure they ground out a result with some determined defending.
They are now nicely placed in the League Two table, heading into next week's FA Cup tie against Accrington Stanley.
Chances were at a premium in the early part of the game, with Lapslie having a cross plucked off his head by the keeper after eleven minutes.
With twenty-five on the clock, Luke Norris' header looked goalbound, but it was deflected wide for a corner. From the set piece, Szmodics' driven cross was held by Vigouroux.
At the other end, McGlashan forced a save out of Gilmartin, before the U's had an appeal for a penalty turned down as Nouble's cross looked like it might have been handled.
There was a serious injury worry for the U's on the stroke of half time, as Norris went down clutching his ankle, and was taken off in a stretcher and off to hospital.
But spirits were lifted somewhat before the break, as Szmodics hit a firm sidefoot beyond the keeper to give the U's a half time lead.
They almost doubled their advantage on the hour mark, as Lapslie slid the ball to Pell, who drove just wide of the target.
Jackson then had a shot parried away by Vigouroux as the right back sought another goal.
The visitors made three quick changes and it swung the game in their favour for a spell in the middle of the half and Gilmartin pulled off a superb stop from Smith's low shot.
Then a lovely flowing move ended with Anderson sweeping a shot beyond the far post.
The U's repelled that period of play and saw Nouble have a shot blocked with ten minutes to go.
The remaining period of the game saw the U's defend strongly and, as per the week before, use their experience to put the ball into good areas to win throws well away from their goal.
And they saw off that last few minutes expertly, to pick up another three points to strengthen their promotion claims once again.
Attendance: 3,227 (314 away fans)