Eye color might be a factor in the success of a US presidential candidate. Less than 17% of people in the United States have blue eyes, but all but six of the first 43 presidents are believed to have had blue or gray eyes. Only five — Richard Nixon, Lyndon B. Johnson, Chester A. Arthur, Andrew Johnson and John Quincy Adams — had brown eyes. Nobody is quite sure as to why this is, although some people have suggested that blue eyes might be considered more attractive than brown, black or hazel eyes. It is important to note that there is a wide range of eye colors, and when it comes to presidents who served before color photography, their exact eye colors are not easy to determine.

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