In a blender or food processor, whirl cantaloupe, peach, peach nectar, white Zinfandel, and lemon juice until smooth. Taste and add sugar if desired.
Pour soup into a container, cover, and chill until cold, at least 1 hour, or up to 1 day. To chill faster, nest container in a bowl of ice water and stir soup often until cold, about 30 minutes.
Pour the soup into shallow bowls. Scatter raspberries on top. Garnish with mint sprigs.