Caretaker manager Gary Bowyer described the Ewood Park crowd as "awesome" as Blackburn eased their relegation fears with a second home win in four days.
Jordan Rhodes's first-half goal was and kept Rovers two points above the drop zone.
"The fans were tremendous and played their part. That's as loud as I've heard Ewood Park for a long time," Bowyer told BBC Radio Lancashire.
"We'll need that support for the last four games of the season."
Average home attendances have dropped by around 8,000 from last season while Rovers were playing in the Premier League, while there has been constant discontent from a majority of fans because of the club's performance on and off the field.
A crowd of 15,317 watched Blackburn follow up their with another success, this time against one of their closest rivals near the foot of the Championship.
And, once again, it was striker Rhodes who proved the difference. The Scotland international has contributed 24 of Blackburn's 51 league goals this season and found the net again on Tuesday against
"It was a great finish," added Bowyer, who is in his second spell in temporary charge this season. "It's why the club paid the money for him.
"We've got to get him to 30 goals [Rhodes has 27 at club level in 2012-13], if not more, between now and the end of the season. He's been tremendous with his contribution to the club."