To make the crust: stir together the cracker crumbs, sugar and melted butter. Press the crumbs into a 9-inch pie pan that's at least 1 1/2 inches deep. Bake the crust for 7 to 9 minutes, until it's barely beginning to color.
To make the filling: mix the sugar and clear jel, then blend into the softened cream cheese until smooth. Add the vanilla, then the eggs, stirring until blended.
Pour the batter into the crust. Dollop the jam over the batter. Use a small spoon to turn and swirl the jam into the batter.
Bake the cheesecake for about 40 to 45 minutes; the center will read 160 degrees on an instant-read thermometer and will still seem soft and "jiggly." Remove from the oven and cool to room temperature, then refrigerate. Serve topped with fresh raspberries and whipped cream, if desired.