Romney, Santorum, and Gingrich all have a reason to compete in must-win state
                                
                                
                                    (Newser) -
                                    With  Arizona  and  Michigan  in the books, the countdown to "Super Tuesday" has begun. But not all of the March 6 states are created equal. Expect the campaigns to set up shop in Ohio, a state without which, the  Washington Post  points out, no Republican president has ever been...