Obama given support by Clinton
The former US president Bill Clinton has given a rousing speech supporting Barack Obama to be re-elected.
Clinton said Obama was the best man to lead America and that he would sort out the country's money problems.
Clinton's wife, Hillary, is also a senior politician and works for Obama's government.
Obama will compete with Republican Mitt Romney in November's presidential election.
Watch the clip to see how popular Bill Clinton was with the crowd.