Rub the rims of 6 champagne flutes with an orange wedge an dip in red sugar; set aside. Pulse cranberries and juice in a food processor until berries are coarsely chopped. Simmer in a saucepan over medium heat with sugar, orange rind and orange juice until syrupy, about 10 minutes. Strain; cool syrup to room temperature. Pour 1-2 tablespoons of syrup into each champagne flute, then top with sparkling wine Garnish with whole cranberries and orange twists if desired.