Former Republican presidential hopeful Rick Santorum is to make his first appearance on \"Late Show with David Letterman\" in New York next week, CBS said. Santorum will be a guest on Wednesday\'s edition of the chat program. \"Santorum, who served as a U.S. Representative from Pennsylvania from 1991 to 1995 and later as U.S. Senator from the state from 1995 to 2007, is the author of the new book \'American Patriots: Answering the Call to Freedom,\' which will be released the day before his \'Late Show\' appearance,\" CBS said in a news release. \"The book shares the true-life accounts of 25 unsung heroic men and women from the Revolutionary War era who fought and sacrificed to give future generations the freedoms enjoyed by the country today.\"