Re-elected Obama vows: Best to come
Re-elected US president Barack Obama has told ecstatic supporters the "best is yet to come" in a victory speech in his home city of Chicago.
Flanked by wife Michelle and daughters Malia And Sasha, the jubilant Democrat congratulated opponent Mitt Romney on a "hard fought campaign" and revealed he would work with the former Massachusetts governor to take the country forward.
The president told the crowd, who chanted "four more years" as he arrived on stage, that they had "lifted me up the whole way and I will always be grateful". And he heaped praise on his family, revealing he had never loved his wife Michelle more and commending his "smart, beautiful" daughters.
President Obama vowed to revive America's economy but warned "progress will come in fits and starts".
Rival Mitt Romney earlier conceded defeat, phoning the president to congratulate him on his victory.
He told his supporters he and running mate Paul Ryan had "given our all" to the campaign and said he wished his Democrat opponent well. The businessman urged his supporters to pray for the re-elected president as he returns to the White House against a backdrop of economic gloom.
In a speech lasting almost 25 minutes, Obama insisted he had hope for the future but admitted there was "more work to do". He told the crowd: "The best is yet to come, but we have more work to do."
Although polls put the two candidates neck and neck, Obama secured a convincing victory. Under the electoral college system, which allots votes to states according to population size, he has 303 while Romney is on 206, with Florida yet to declare.
After it became clear the Republican candidate could not win, the president took to Twitter to tell followers "four more years".
He added: "Tonight, more than 200 years after a former colony won the right to determine its own destiny, the task of perfecting our union moves forward. Tonight, in this election, you, the American people, reminded us that while our road has been hard, while our journey has been long, we have picked ourselves up, we have fought our way back, and we know in our hearts that for the United States of America, the best is yet to come."