Last season's corresponding fixture represented a low point for AFC Blackpool as they were hammered 7-0 at Chadderton.
What a difference nine months make as Blackpool are now in fine form and this win lifted them to fourth in the Hallmark Security League first division.
AFC were without the suspended Danny Pickering and Fran Donaghy, and Chadderton had the better of the early chances, though Martin Baird was dominant in defence for the visitors.
On 32 minutes, McKenna collected the ball on the right, beat his man and fired a low ball towards the penalty spot, which was turned in by a defender for an own goal.
The goal settled AFC, who had their best spell of the game in the run-up to half-time as Cassidy and Hargreaves bossed midfield.
It was no surprise when Blackpool doubled their lead on 39 minutes, Baird finding the far corner with a low drive.
Chadderton put AFC on the back foot after half-time and deservedly pulled one back on 55 minutes,when a deflected shot left Povey flat-footed and went in for an own goal.
They went close to an equaliser when a curling shot struck an upright and it took some excellent saves from Pavey to keep Chadderton out.
Three weeks without a game seemed to be taking its toll on AFC as Chadderton pushed further forward.
However, AFC stood firm in a nailbiting final 20 minutes and sealed victory on 88 minutes, when Carnan Dawson made a lung-busting run down the right and crossed for Jack Williams in the box. The ball looped off a defender for Conah Bishop to head into the far corner.
On Boxing Day Blackpool host second-placed Litherland REMYCA in confident mood after collecting 15 points out of 18.
AFC Blackpool: Povey, Nay, Baird, Caunce, Betteridge, Bishop, Cassidy, Hargreaves, Gregory, Duffield, McKenna. Merry Christmas Mick Downer