The wall in the Hamburg Inn No. 2 in Iowa City, Iowa is shown with past campaign buttons, stickers and newspaper clippings. Famous for its "Coffee Bean Caucus" the Hamburg Inn is a must-stop location for presidential hopefuls seeking a nod in the Iowa caucuses.
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President Ronald Reagan waved to a crowd of nearly 8,000 people, Feb. 20, 1984 in Waterloo, Iowa. The Waterloo stop was the first of two Iowa stops on the day of the Iowa caucuses.
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Republican presidential hopeful Bob Dole with wife Elizabeth at a rally on Feb. 12, 1996, in Des Moines, Iowa. Dole finished first in the Iowa caucuses.
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Democratic presidential candidate and former Vermont Gov. Howard Dean yells while addressing supporters during his caucus night party in West Des Moines, Iowa on Jan. 19, 2004.
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Democratic presidential hopeful and former Massachusetts Sen. John Kerry celebrates after winning the Iowa caucus vote Jan. 19, 2004 in Des Moines, Iowa.
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Texas governor and presidential hopeful George W. Bush serves coffee to patrons at a pharmacy coffee shop during a visit to Grinnell, Iowa, Jan. 21, 2000.
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Democratic presidential hopeful Al Gore walks with family farmers on the Menz family farm in Perry, Iowa on Jan. 21, 2000.
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Illinois Senator Barack Obama stretches his neck as he huddles with his senior campaign staff in the school locker room after speaking to voters at a rally Jan. 1, 2008 in Des Moines, Iowa.
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Republican presidential candidate Mitt Romney speaks during a meeting with voters at Music Man Square in Mason City, Iowa on Dec. 29, 2011. Romney seized the lead in Iowa before the state's caucus kicks off voting to decide the Republican presidential nominee.
Republican presidential hopeful Sen. John McCain (2nd from left) and his entourage board a private jet following a rally at the Dubuque Jet Center Jan. 2, 2008. He was campaigning throughout Iowa trying to win over voters on this last full day of campaigning before the Jan. 3 caucus.
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