A couple kiss in a sea of Obama supporters at Grant Park in Chicago.
If he wins, Obama will be the third Illinois resident to occupy the White House after Abraham Lincoln and Ulysses S Grant. He will also be the first Hawaii-born American to be President of the United States. Hawaii became part of the US in 1959, two years before Obama was born on August 4, 1961.
Photograph: Timothy A Clary/AFP/Getty Images
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