Heat oil in a large Dutch oven over medium heat. Add onion and garlic; cook 4 minutes or until onion is tender, stirring occasionally. Add juice and next 5 ingredients (through tomatoes); bring to a boil. Cover, reduce heat, and simmer 8 minutes or until shells open. Remove clams from pan. Discard any unopened shells. Add parsley to pan; cook until liquid is reduced to 4 cups (about 15 minutes). Serve clams and sauce over pasta.