Kennedy, back in the starting line-up, described Saturday's 2-1 win at fellow strugglers Colchester as a "dogfight" as Brian Laws' side climbed out of the relegation zone for the first time since October.
"It's been a gradual increase in performance from the lads," Kennedy told the club's official website. "Everyone's being working really hard, especially in training.
"On Saturday, we won the dogfight. It's a great feeling when you've all battled hard and come away with three points.
"To get out of the bottom four is an added bonus. But now everyone has to keep calm. We've got Portsmouth on Saturday, so we need to make sure that we win that again."
Scunthorpe are unbeaten in their last three league games, following up home draws with Oldham and Shrewsbury with a fifth league win on the road at Colchester.
Kennedy added: "Obviously they're down there with us and we said before the game that this could be one of the biggest games for us at a crucial period. To get the three points is exactly what we wanted."