Labor MPs need to get over the idea that Kevin Rudd is the messiah who could win the next election, Attorney-General Nicola Roxon says.
Ms Roxon, a strong supporter of Prime Minister Julia Gillard, says Mr Rudd has many strengths and achievements but his recent conduct has been extremely unhelpful.
'We need to get out of this idea that Kevin is a messiah who will deliver an election back to us. That is just, I think, fanciful,' she told ABC television.
It wouldn't be good for the country to have Mr Rudd as prime minister again, Ms Roxon said.
'He was very difficult to work with. There were a lot of challenges,' she said, referring to Mr Rudd's time in the top job and his rolling by Ms Gillard 20 months ago.
'People might say that we were too polite ultimately abut the way we did it. We didn't air all our dirty linen. I don't really want to air it now, but the truth is that decision was made for very strongly-held reasons that are just as important now.
'Government has to be able to function properly so we can deliver for the community.'
Ms Roxon said a leadership vote, most likely to be held on Monday, should bring an end to the saga that reached fever pitch on Wednesday night when Mr Rudd announced in Washington he was quitting as foreign minister and returning to Brisbane to discuss his future with his family.
Ms Roxon said Mr Rudd's supporters claim 40 votes in the 103-member caucus.
'But I frankly would be surprised if that's the case. Ultimately this is now the way to test that. We have to put this issue to bed,' she said.
It would be a disaster if Mr Rudd lost the ballot and then went to the backbench to continue destabilising the government even further.
'We have got to be mature. There's a vote. Someone will win the vote and then we need to get on with doing our good job in government,' Ms Roxon said.
