Campbell is battling to keep the club in the Football League.
He told the Mirror: “I think it will go to the wire. I think it'll go right to the wire. It's about character now. Yes, of course there's some tactical decisions, players being fit but this comes down to character. What do you want out of football? How can you apply yourself on and pff the pitch.
“Making sure you are focused, sleep, putting everything into training to make sure you are ready for the games. Attitude, desire, spirit and your soul. That's how I was. We need to really step up as individuals. We need to get going, get motivated, make sure we are ready for every battle."