1. Preheat oven to 350 degrees F. For crust, combine crushed crackers and powdered sugar; stir in melted butter. Press onto bottom and about 2 inches up sides of a 9-inch springform pan. Set aside.
2. In a small bowl stir together 1 cup of the raspberries and the granulated sugar. Set aside. For filling, in a large mixing bowl beat cream cheese and condensed milk with an electric mixer until combined. Add eggs and vanilla; beat just until combined. Divide batter in half. Stir melted chocolate into half of the batter. Pour chocolate batter into crust-lined pan. Stir raspberry-sugar mixture into remaining batter. Spoon raspberry batter over chocolate batter.
3. Place pan on a shallow baking pan. Bake for 50 to 60 minutes or until center appears nearly set when pan is gently shaken. Cool in pan on a wire rack for 15 minutes. Loosen crust from sides of pan. Cool 30 minutes. Remove sides of pan; cool cake completely. Cover; chill at least 4 hours. Serve with remaining raspberries. Makes 16 servings.