Make the cranberry simple syrup by heating 1 cup of whole cranberries, 1 cup of sweetener or sugar, and 1 cup of water over low to medium low heat until sugar dissolves and cranberries begin to burst. Remove from heat and strain, reserving cranberries if desired. Let liquid chill in fridge for an hour prior to using.
Add the cranberry simple syrup to a pitcher along with vodka, reserved cranberries (or can use new whole ones if desired), and champagne. Stir to combine.
Dip the top of champagne flutes into water. Press the rim into sugar to garnish. Pour the drinks into the prepared champagne glasses, garnish with a splash of Sprite or club soda. Garnish with sugared rosemary. Make sugared rosemary by dampening rosemary and rolling in sugar.
Enjoy.
Notes
*if you can't find cranberry vodka, use plain or vanilla vodka
** you could substitute cranberry juice cocktail in this. Use the cocktail kind for extra sweetness