How to Make It
Combine 1 cup of the water, and 1 cup of the granulated sugar in a microwavable glass bowl; microwave until sugar is dissolved, about 1 minute. Add 1 cup of the cranberries, and let stand 20 minutes. Place superfine sugar on a plate. Drain and discard liquid; roll soaked cranberries in superfine sugar to coat. Set aside.
Combine 1 cup of the water, and remaining 3 cups cranberries and 1/2 cup granulated sugar in a medium saucepan over medium-high, and bring to a boil. Reduce heat to medium-low, and simmer for 10 minutes. Strain through a fine mesh sieve, and discard pulp.
Stir together cranberry syrup, limeade, vodka, and remaining 3 cups water in a pitcher. Pour over glasses of crushed ice, and top each with a splash of soft drink. Garnish with sugared cranberries and lime slices.