Blagojevich planned to close Pontiac prison last December and move its inmates to a largely unused prison in Thomson. An injunction has kept the prison open.
McCoy says officials want the letter writers to be respectful in their comments to Quinn, who he pointed out Tuesday should be treated with the respect he will give those seeking to save Pontiac prison.
Quinn has not said he would reverse Blagojevich's efforts to close the prison. However, he said last week he would order a review of the plan.