Preheat oven to 325°.
Coat a 9-inch round cake pan with cooking spray; line bottom of pan with wax paper. Coat wax paper with cooking spray.
Combine corn and next 5 ingredients (corn through eggs) in a blender or food processor; process until smooth.
Lightly spoon 2 cups flour into dry measuring cups; level with a knife. Combine 2 cups flour, granulated sugar, baking powder, salt, and baking soda in a large bowl; stir well with a whisk. Add corn mixture to flour mixture, stirring just until combined.
Toss raspberries with 2 tablespoons flour; fold into batter. Pour batter into prepared pan. Bake at 325° for 1 hour or until a wooden pick inserted in center comes out clean. Cool in pan 10 minutes on a wire rack. Remove from pan and carefully peel off wax paper. Cool completely on wire rack. Sprinkle with powdered sugar, if desired.