President Barack Obama said his success in attaining the US's highest political office is a testament to the dedication of Martin Luther King and other civil rights activists.
Later today, Obama will speak on the same spot that King delivered his famous I Have a Dream speech 50 years ago.
"When you are talking about Dr. King's speech at the March on Washington, you're talking about one of the maybe five greatest speeches in American history," Obama said in a radio interview yesterday.
"And the words that he spoke at that particular moment, with so much at stake, and the way in which he captured the hopes and dreams of an entire generation I think is unmatched."
Tens of thousands of Americans have gathered in Washington to mark 50 years since Martin Luther King made his I Have a Dream speech.
Today marks 50 years since Martin Luther King's famous I Have a Dream speech - but how far has America come in realising that dream?