In food processor with knife blade attached or in a blender a medium speed, gramham crackers until fine crurmbs are formed.
Preheat over to 325 degrees.
In Springform pan, with fork, stire graham cfracker crumbs and melted margarine or butter until moist. With hand, press into springform pan. Bake for 10 minutes. Cool on wire rack.
In large bowl, mix on medium speed, cream cheese until smooth, add sugar slowly. Beat in brandy, vanilla extract, and eggs until well blended.
In seperate bowl, mix pumpkin, cornsarch, cinnamon, allspece and salt. Stir half of cream cheese misture into pumpkin misture until blended. Stir sour cream into remaining cream cheese mixture.
Reserve 1/2 cup of pumpkin mixture. Pour remaining pumpkin misture onto graham cracker crust. Carefully pour cream cheese mixture on top of pumpkin layer. Spoon dollops of reserved pumpkin misture onto cream cheese layer. With knife, cut and twist through the cream cheese layer to obtain the swirl effect.
Bake cheesecake for 1 hour. Turn off oven and let sit in oven 1 hour longer. Remove cheesecake from oven. With a small knife, loosesn cheesecake from side of pan to prevent ccracking . Cool completely. Cover and refrigerate cheesecake at tleast 6 hourse or overnight before serving.