Barack Obama US election victory speech video

President Barack Obama secured a second term in the White House, beating Republican challenger Mitt Romney, after winning the crucial battleground state of Ohio which helped him surpass the 270 mark of required electoral votes, according to projections.

"We're all in this together. That's how we campaigned, and that's who we are. Thank you," Obama wrote in a message on the social networking website Twitter, moments after American news networks projected his re-election.

In his victory speech before supporters in Chicago, Mr Obama said he would talk to Mr Romney about "where we can work together to move this country forward".

Mr Obama prevailed despite lingering dissatisfaction with the economy and a hard-fought challenge by Mr Romney.

His Democrats also retained their majority in the Senate, which they have held since 2007, while Republicans kept control of the House.

Prime Minister David Cameron has sent his congratulations to the president.

"I think he's a very successful US president and I look forward to working with him in the future," he said.

Labour leader Ed Miliband said Mr Obama's victory was built on creating a "fairer economy".

Click on the video opposite for his victory speech.