Heat cranberry juice cocktail to boiling in a saucepan. Remove from heat and stir in raspberry gelatin until dissolved; transfer to a large mixing bowl. Using an electric mixer on high speed, beat cranberry sauce in a small bowl for 1 minute. Stir into gelatin mixture. Chill until mixture begins to thicken, but not set.
Gently mix in whipped topping, using a rubber scraper. Spoon into serving dishes or prepared pie shell. Chill until firm.