Place sugar on plate. Wet the rim of the glasses with a water moistened paper towel. Press moistened edge into sugar.
In blender combine cranberry juice, remaining sugar. 6-7 cups ice and rum. Peel one clementine and squeeze juice into blender. Turn blender on medium for 30 second or so; just enough to mix the ingredients and break up some of the ice.
Slice remaining clementine in thin rounds. Divide cranberry mixture between glasses and garnish with orange slices and fresh cranberries.