A few days before Christmas, former Vice President Dick Cheney emerged from several months of a self-imposed political sabbatical to headline a fundraiser for Maria Cino, a party operative and Bush administration official who is running to replace Michael Steele as head of the Republican National Committee. The fundraiser for Cino, held at the Alexandria, Va., home of Cheney's former aide Mary Matalin, was his first major foray into partisan Washington political theater since receiving a mechanical heart pump in July that has, most doctors say, saved Cheney's life by taking on the task of helping to push blood through...