Excerpt from Playbook 2012: Inside the Circus by Mike Allen and Evan Thomas:
Over the long campaign, as the lead position in national polls changed a half-dozen times (Bachmann, Perry, Cain, Gingrich, and Santorum all led at one time or another), a top Romney aide told us that he saw the GOP nominating campaign as a takeoff on J. R. R. Tolkien’s Lord of the Rings. In the books, and later the movies, the Ring of Power was too powerful to handle for anyone but Sauron, the Dark Lord, who embodied evil. The nomination was like the Ring of Power, he said. Each time someone thought he had grasped it, he began behaving foolishly and doomed himself. In early January, after Romney won easily in New Hampshire, his camp had relaxed for a moment and let itself believe that the fight was essentially over, that Romney had grasped the ring and wrapped up the nomination. The campaign began to run only positive ads. Then the candidate stumbled badly in the week before South Carolina. And with that, the campaign went back to negative ads.