Walgreens' new 27,000-square-foot downtown Chicago location has a wine collection of more than 700 bottles, including one that sells for $500. The company says its flagship store with a European market feel is meant to be a destination to distinguish the chain's brand. David Schaper/NPR hide caption

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Gingrich with one of the many pieces of farm equipment he encountered on a last-minute campaign swing through Iowa. This tractor was on display at the Heartland Acres Agribition Center on Monday in Independence, Iowa. Andrew Burton/Getty Images hide caption

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A young Mitt Romney supporter holds yard signs Thursday at a campaign event at J's Homestyle Cooking in Cedar Falls, Iowa. Chip Somodevilla/Getty Images hide caption

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A volunteer arranges buttons before Mitt Romney speaks Wednesday in Clinton, Iowa. Chris Carlson/Associated Press hide caption

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A young supporter backs former Massachusetts Gov. Mitt Romney as he speaks on Wednesday at Homer's Deli and Bakery in Clinton, Iowa. Chris Carlson/Associated Press hide caption

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Texas Gov. Rick Perry speaks at a campaign event at Clark Electric Co-op on Dec. 27 in Osceola, Iowa. Perry's stance on immigration has troubled some Iowa voters. Justin Sullivan/Getty Images hide caption

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