Democratic presidential candidate, Barack Obama has asked his finance team to help his former opponent Hillary Clinton pay off a debt of at least $10m (£6m) from her failed presidential campaign.

In a teleconference with his top fundraisers yesterday afternoon, Obama asked them to help the former first lady, a campaign spokesman confirmed.

Later at a star-studded fundraising gala in Los Angeles, the Illinois senator, who could become America's first black president, appealed to those in the crowd who might have supported Clinton.

"I know I caused some heartburn and some frustration," he said, adding that he and Clinton "were allies then and we're allies now."

Obama's campaign refused to say how many millions he and the Democratic National Committee (DNC) raised at the gala, but Democratic officials put the number at close to $5m. The presidential hopeful had already broken fundraising records by the end of May by raising an unprecedented $287m.

The price of a ticket for the gala's general reception was $2,300 while tickets to the VIP dinner cost $28,500. The DNC will get the latter donations and Obama will receive the $2,300 share.

Obama also used the event to reach out to Hollywood stars to throw their support and cash behind him.

Many celebrities attended including actors Don Cheadle and Dennis Quaid, boxer Sugar Ray Leonard, and Black Eyed Peas frontman Will.i.am, who created two music videos for Obama during the primary campaign.