Swindon had a point to prove after their defeat at the County Ground and they shaded the first half of the contest with good efforts from Eric Sabin and Matt Heywood.
Town were generally unruffled, however, and were cheered on by the home fans who had positioned themslves in the South Stand after Kenny Irons had opened the scoring with an unexpected goal.
Irons hit a powerful 25 yard effort straight at Bart Griemink in the Swindon goal - it looked as though it would be easily dealt with but the Dutchman lost concentration and the ball squirmed out of his hands and trickled over the goal line.
The goal was an unexpected bonus for the Terriers, certainly for the fans in the stands, who were only finding outlets through Irons and John Thorrington.
It was a good start for Town who had struggled to find their rhythym with Danny Schofield and Leon Knight both having quiet first halves.
Things changed after the break as Town started stringing passes together and pressurising their visitors.
Steve Jenkins felt hard done by as he was denied a penalty appeal in the opening minutes of the second half after he had been brought down in the Swindon area.
Minutes later, Leon Knight extended the slender Town lead when he slipped behind Bart Griemink to find the net with a downward header after Danny Schofield finally found some space on the left flank and flicked in a right footed cross which found its target.
Town improved throughout the second half and always seemed comfortable despite the odd foray by Swindon players, notably Eric Sabin, who was brought down by Kevin Gray as he raced to latch onto a long ball.
By the time the final whistle had gone, news of Oldham's defeat at Wigan meant that the Terriers had gone up to 6th - back into the play-offs.
Not a great performance, especially as conditions changed throughout the match, but Town will take the points gratefully.
Read Doug Thomson's match report in the Examiner on Monday. Have your say on the match and Town's play-off prospects in the message board below. Selected comments may be published in the Examiner.
Town (4-4-2): Margetson, Jenkins, Clarke, Evans, Gray (Moses 79), Thorrington (Heary 86), Schofield, Holland, Irons, Facey, Knight (Wijnhard 86)
Subs not used: P. Senior, Hay
Booked: Gray, Knight
Scorers: Irons 21, Knight 50
Swindon (4-4-2): Griemink, Hewlett, Gurney, Howe (Edwards 74), Grazioli, Duke, Sabin, Invincible (Young 54), Heywood, Robinson, Willis
Subs not used: McKinney, Halliday, Herring
Booked: Sabin, Heywood, Willis
Referee: Mark Cowburn (Blackpool)
Attendance: 9,569 (358 Away Fans; 798 Town fans occupied the South Stand)
Match points follow on subsequent pages.
92 mins: Facey's late shot was wide.
89 mins: Schofield and Facey combined but couldn't get past the Swindon defence.
87 mins: Lou Macari opted for a double substitution and brought on Clyde Wijnhard and Thomas Heary for Leon Knight and John Thorrington - both players went off to a round of applause.
86 mins: Knight looked tired as produced a daisy-cutter when he meant a flighted effort.
84 mins: Knight crossed to the far side but went out of play before any Town players could arrive to meet it.
80 mins: Evans laid the ball on for Schofield and he set up Leon Knight for a shot which flashed past the left hand post of Griemink.
78 mins: Swindon won a corner but Gray headed it away. Town seemed comfortable with their lead as Lou Macari prepared a substitution - Adrian Moses came on for Kevin Gray.
73 mins: Swindon won a free kick in a dangerous area but the shot was high over Margetson's bar. Swindon had been pushed right back by a more hungry looking Town who had come out to win during the second half.
70 mins: Schofield's movement opened up the opportunity for a curler which Heywood cleared off his line at the expense of a corner.
68 mins: Jenkins evaded a tackle under pressure and passed to Kenny Irons.
67 mins: Holland went on a rangy run but lost the ball as he closed in on the Swindon area.
64 mins: Hailstones and rain lashed the McAlpine as they continued to press.
63 mins: Knight lined up a shot but it was stright at Griemink after Gray's ball put him through.
59 mins: Kevin Gray tripped Sabin as both players chased a long ball down. Gray wasn't the last man so he was only booked.
57 mins: Griemink collected a sliding tester from Facey.
55 mins: Sabin headed a curler from Knight behind for a corner. Town were attracting cheers from the South Stand.
52 mins: Kenny Irons hit a sizzler which Griemink had to save!
50 mins: Leon Knight slipped behind Griemink and powered Schofield's curled cross into the back of the net with a sublime header.
48 mins: Knight dashed upfield on the counter-attack with Facey and Schofield in support. Jenkins appeared to have been tripped in the area after Leon Knight was felled in the centre of the pitch by Gurney after spreading the play. Jenkins argued his case for a penalty vociferously.
A poor match was at least illuminated by Kenny Irons' 21st minute goal. The Terriers were generally poor, though on one of their few chances Kenny Irons opted to speculate with a 30 yarder which Bart Griemink appeared to have under control before he lost concentration and allowed the ball to trickle over his line.
There was little cheer for Town fans as Swindon seemed dangerous enough to score with Sabin shooting over Margetson's bar and Matt Heywood heading over the bar.
46 mins: Facey went past Gurney on a Town counter-attack and won a corner after his attempted cross for Knight was put behind.
45 mins: Knight was booked for an needless foul right in sight of the referee.
44 mins: Duke miscontrolled a promising pass.
41 mins: An early cross saw Knight head beyond the 'keeper but also beyond the post. Willis was booked for dropping Irons with a late challenge.
40 mins: Sabin was offside as Swindon tried to inject some excitement into the game.
39 mins: Facey was hashly penalised for backing in. The match was poor fayre.
33 mins: Knight tried a cross/shot but it was wide as he latched onto the end of a Town through ball.
31 mins: Thorrington glared at a Swindon player after he was brought down by a very late challenge.
30 mins: Gray headed a Swindon attack clear but Evans had to concede another corner as Town dropped deep again with Swindon pushing.
29 mins: Howe and Gurney challenged at a set piece with Clarke missing.
26 mins: Swindon were pushing for an equaliser, and Sabin was booked for shirt-pulling on John Thorrington as Town appeared to be defending deep again.
21 mins: Irons cannoned a 30 yards shot which squirmed out of the hands of Bart Griemink and trickled into the back of his net!
20 mins: Thorrington won a corner after Irons set him free - the American went up the pitch and tested the Swindon defence.
19 mins: Howe crossed for Sabin but Clarke was quick to tackle him as Swindon enjoyed a long passage of possession.
14 mins: After a great start the game had become scrappy and poor again.
8 mins: Danny Schofield hammered a shot in but it was palmed away.
7 mins: John Thorrington blazed a trail to the byline, with support from Jenkins, and crossed. Swindon put the ball out for a corner which the American teased the Swindon defenders with twice.
5 mins: Facey went round one challenge but a second player caught him and brought him down. It was a rare Town attack after pressure from Swindon had seen them win the majority of the early possession.
1 min: Town kicked off with all sides of the McAlpine cheering them on.