Kevin Rudd has ousted Prime Minister Julia Gillard as leader of Australia's Labor Party.

He won 57 votes in a leadership ballot called by Ms Gillard, who received 45 votes.

The change comes ahead of an election called for 14 September, which polls suggest Labor is set to lose.

Mr Rudd is more popular with voters than Ms Gillard, and many believe Labor will perform better in the election under him.

Richard Galpin reports.