The Republic of Ireland international scored twice during Saturday's 3-1 home win over Sheffield United and North End now lie just four points of safety. They face Millwall, Cardiff, Ipswich and Watford in their last four outings, with Treacy still confident his team can survive.
He said: "The players have always had the belief we are going to stay up.
"Hopefully the crowd will stay the way they are and the people round Preston will think we will stay up.
"If we win three out of four it should be enough but it's easier said than done."