CANBERRA (AP) - Three Australian government ministers have quit their portfolios in the continuing fallout from a bungled leadership showdown that reinforces perceptions of a crisis in Prime Minister Julia Gillard's administration six months before national elections.

Cabinet ministers Chris Bowen and Martin Ferguson as well as Kim Carr, who was a minister outside Cabinet, resigned on Friday over their support for Ms Gillard's rival, former Prime Minister Kevin Rudd.

Ms Gillard on Thursday called a leadership ballot of ruling Labor Party lawmakers after weeks of leadership speculation.

Mr Rudd decided against running, although his supporters say the result of a ballot would have been close.

Senior minister Simon Crean, who demanded the ballot, was sacked by Ms Gillard and junior minister Richard Marles, a Rudd backer, resigned on Thursday.