Obama greets his adoring supporters in Chicago

A silhouette of a person standing on the stage during preparations for the election night gathering in Grant Park Photograph: Justin Sullivan/Getty

A worker cleans plates of bulletproof glass on the stage before Barack Obama speaks to the Grant Park crowd Photograph: Jewel Samad/EPA

Obama supporters run across a field shortly after the gates open at Grant Park Photograph: Shawn Thew/EPA

Obama supporters cheer on their candidate before his victory speech Photograph: Jewel Samad/AFP

Caroline Olivia Wolf reacts to the early poll results Photograph: Michal Czerwonka/Getty

A multiple exposure of the crowd gathered at Grant Park Photograph: Jewel Samad/AFP

The Chicago crowd reacts as television networks project Obama as the election winner Photograph: Saul Loeb/AFP

CNN predicts Barack Obama is the winner, and Grant Park goes wild Photograph: Tannen Maury/EPA

Television presenter Oprah Winfrey (centre) cheers with fellow Obama supporters Photograph: Shawn Thew/EPA

The Rev Jesse Jackson reacts after projections show an Obama victory Photograph: Joe Raedle/Getty

An Obama supporter holds an American flag and a pin proclaiming 'I voted Obama' Photograph: Eric Thayer/Getty

Chicago Democrats realise that after the longest, most expensive presidential campaign in memory, their candidate has won the election Photograph: Justin Sullivan/Getty

The sea of Obama supporters at Grant Park Photograph: Stan Honda/AFP

A shirt shows the face of the next president of the United States Photograph: Eric Thayer/Getty

A man weeps as the results dawn on the Grant Park crowd Photograph: Shawn Thew/EPA

Supporters watch the election results roll in on a giant screen Photograph: Stan Honda/AFP

Barack Obama arrives to speak to his supporters with his wife, Michelle, and their children, Malia and Sasha Photograph: Gary Hershorn/Reuters

The next first family walk on stage to be greeted by their supporters in Chicago Photograph: Shawn Thew/EPA

Barack and Michelle Obama join his running mate, Joe Biden, and his wife, Jill, after Obama's victory speech Photograph: Eric Thayer/Getty

Obama delivers his victory speech Photograph: Jason Reed/Reuters

President-elect Barack Obama addresses supporters Photograph: Jewel Samad/AFP/Getty

Barack and Michelle Obama embrace on stage Photograph: Stan Honda/AFP

Michelle Obama and Jill Biden acknowledge the crowd after the victory speech Photograph: Chris McGrath/Getty

Barack Obama and his daughter Sasha stand on stage Photograph: Chris McGrath/Getty