The Gingrich campaign releases a new web ad attacking Mitt Romney, highlighting past, negative comments from John McCain, Mike Huckabee, and Fred Thompson about him:

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UPDATE: Romney spokeswoman Andrea Saul e-mails this response: “Speaker Gingrich is an unreliable conservative leader and he’s doing everything he can to try to distract from that fact. Those who know him best are not supporting him. Anyone who wants to learn more about his undisciplined leadership directly from those who served with him can do so at unreliableleader.com or undisciplinedleader.com.”