I think it comes down to the kind of campaign he has run, and the dynamics of the Not-Romney candidates running against him. Romney entered the race as the odds-on favorite, forcing the other candidates to organize around his candidacy. But rather than focus on his record, the Not-Romneys focused on stopping each other, giving Romney the space to attack them at times of his choosing. And he has. As various Not-Romneys have emerged, they have been slammed and smeared with negative MSM stories about everything from a rock in west Texas to sexual misconduct. Rick Santorum is the latest, with this bizarre story about his wife having lived with the abortion providing doctor who delivered her, before meeting and marrying Santorum. Challenger rises, gets whacked in the MSM.

This pattern is too obvious to ignore. Add in the fact that only Romney had five years and the money and the staff to build up books on every conceivable opponent, and you have enough evidence to make a Clue accusation: It was the former Massachusetts governor, in the mainstream media, with an oppo research dump.