Republican presidential candidates former Massachusetts Gov. Mitt Romney, left, and Texas Gov. Rick Perry interact during a Republican presidential debate Tuesday, Oct. 18, 2011, in Las Vegas.
Last night's debate was arguably the most contentious yet, and maybe the first in which a candidate actually reached out and touched an opponent during the televised event.
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In a previous debate, Perry appeared to scold Ron Paul during a break.
Mario Anzuoni / Reuters
Texas Governor Rick Perry, left, talks during a break with Rep. Ron Paul on stage at the GOPl primary debate at the Ronald Reagan Presidential Library in Simi Valley, California Sept. 7, 2011.