Perry prepares to speak with voters attending the West Des Moines caucus in Iowa on Jan. 3. Jonathan Gibby/Getty Images hide caption

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Editors of the conservative Dartmouth Review, from left to right: Sterling Beard, 22, from Abilene, Texas, the Review's editor-in-chief; Benjamin Riley, 20, from New York City; Blake Neff, 21, from Sioux Falls, S.D. John W. Poole/NPR hide caption

itoggle caption John W. Poole/NPR

Former Massachusetts Gov. Mitt Romney campaigns Sunday in Council Bluffs, Iowa. Justin Sullivan/Getty Images hide caption

itoggle caption Justin Sullivan/Getty Images