First goals of the season for Luke Hyam and Carlos Edwards helped Town on the way to a second successive win.
Hyam struck on two minutes – the third consecutive game that Blues have scored inside five minutes – with his first goal in over a year.
Jordan Rhodes replied for Blackburn on his first return to Portman Road since leaving the Club in 2009 but Edwards put Blues back in front at the start of the second-half.
Rhodes almost equalised in freak circumstances when Dean Gerken’s clearance bounced back off him and into the sidenetting but Frank Nouble sealed the win five minutes from time when he capitalised on a mistake by Jake Kean to put the ball in the empty net.
Town made four changes to the side that won at Charlton at the weekend, with Stephen Hunt coming in for his first start since joining the Club on a short term deal last month.
Hyam was another addition to the starting line-up having missed the visit to the Valley with a back injury and it took him only four minutes to make his mark, beating Jake Kean from the edge of the box.
Dean Gerken had already saved well from former Town loanee DJ Campbell before Hyam’s strike and the ‘keeper had to be alert again to clear the danger from Rhodes.
Tommy Smith did brilliantly to rob Joshua King inside the Town box after good work by Rhodes, while at the other end Aaron Cresswell zipped a strike over the bar.
Edwards – at full stretch - couldn’t get his header on target from Hunt’s cross before Campbell was booked for a late challenge on Cresswell.
Edwards drove into the sidenetting from 25 yards before Rhodes levelled the scores on the half hour. Town’s defence switched off and the Scotland international rounded Gerken and stroked the
ball into the empty net.
Town responded with Frank Nouble sending in a terrific cross that just beat David McGoldrick, Christophe Berra’s header then hacked clear six yards out in an even first 45 minutes chances wise.
Town edged in front two minutes into the second-half with Edwards finding the net from close range after Hunt had weaved his way into the box.
Berra picked up a yellow card for a foul on King, who was replaced minutes later by Ben Marshall.
Gerken had a heart in mouth time on 70 minutes when his clearance cannoned back off Rhodes and almost into the net.
Rhodes again threatened with a lunging volley that drifted wide, Todd Kane then booked for dragging down McGoldrick as he looked to get clear.
Hunt fired well over from the edge of the box before Campbell was replaced by Rudy Gestede in Rovers’ final change.
Tyrone Mings replaced Hunt, Daryl Murphy also on for McGoldrick and five minutes from time Nouble capitalised on in-decision by ‘keeper Kean and put the ball into the empty net.
The win lifts Town to within two points of the Play-Offs with Huddersfield at Portman Road on Saturday.