Democrat Barack Obama has become the first African-American to claim victory in the United States presidential elections.

Mr Obama proved that his message of “change” was what Americans wanted as voters backed him overwhelmingly in favour of Republican John McCain.

Speaking at a victory rally in his hometown of Chicago, he said: "It's been a long time coming, but tonight... change has come to America.”

Mr Obama, who claimed 338 electoral college votes to McCain’s 156 (as of 6.30am (GMT)), thanked his family, campaign team and, most poignantly, his supporters.

But he sent a warning that with his new title comes responsibility.

"Even as we celebrate tonight, we know the challenges that tomorrow will bring are the greatest of our lifetime - two wars, a planet in peril, the worst financial crisis in a century,” he said.

"The road ahead will be long. Our climb will be steep... But America - I have never been more hopeful than I am tonight that we will get there."

Fears that last minute and undecided voters would abandon Mr Obama in favour of his more experienced rival were shattered as the Democrat took the key battleground states of Ohio and Pennsylvania.

From there, his journey to the White House was comfortable - as California fell, so did the 270 electoral college votes that Mr Obama needed for the White House.