Presidential candidate is a fan of the singer
The Democrat candidate asked the singer to come on board because he feels she appeals to voters.
And Joss, 21, is said to be chuffed that Barack has selected her.
‘Joss is a big supporter of Barack Obama and was very excited to be asked to do this for him,’ a source tells The Sun.
‘He sent a personal message asking her to get on board.
‘He has always admired her music and thinks she is the perfect choice because of her unique appeal to black and white voters.
‘She believes he is going to be the first black American president and she is honoured to be a part of that.’
The Devon-born diva, who spends up to 9 months a year in the States, will release the track in November.
Barack, 47, is up against Republican John McCain.