Mrs. Clinton and Mr. McCain have both derided Mr. Obama as “elitist” for his remarks about bitter rural voters who “cling” to guns and religion, even as Mr. Obama, in a counterpunch, mocked her courtship of gun owners, depicting her as a kind of ersatz Annie Oakley “packing a six-shooter” in a duck blind. And Mr. McCain, throwing a haymaker of his own, pointed out in a recent speech to members of the National Rifle Association that “someone should tell Senator Obama that ducks are usually hunted with shotguns.”