Process half each of first 3 ingredients in a blender until smooth, stopping to scrape down sides. Repeat with remaining apricot halves, nectar, and sugar. Serve over crushed ice with sparkling wine. Garnish, if desired.
*2 (12-ounce) cans ginger ale or lemon-lime soda may be substituted.
Note: You can stir together the apricot mixture and the sparkling wine in a pitcher. Be sure and do this just before serving.