The ABC understands Prime Minister Julia Gillard has lost significant support in the Labor caucus.

It comes after a week in which Labor disunity was on full display in Canberra and former prime minister Kevin Rudd re-emerged very publicly.

ABC Insiders presenter Barrie Cassidy says Mr Rudd is the only figure being considered as an alternative prime minister.

Mr Cassidy spoke about the tensions within the party on Insiders yesterday.

"I am now very strongly of the view that Julia Gillard will not lead Labor into the next election," he said.

"I think there will be a change either by her own hand or the actions of others. And I'm not relying entirely on guesswork here."

Writing for ABC's The Drum, Mr Cassidy says key Labor players are now planning when and how Ms Gillard should be approached to step aside.

"Those who have changed their thinking are convinced that in any case, she must be close to deciding for herself that continuing on through a torrid and hopeless 10-week campaign is intolerable," he wrote.

A spokesman for Workplace Relations Minister Bill Shorten, who is a key figure in Labor's Victorian right faction, says he supports the Prime Minister and that has not changed.

This week Mr Rudd hit the hustings in Victoria to help campaign for the re-election of Labor MPs.

He insisted he did not "see any circumstances" that would elevate him back to the Labor leadership.

He also pledged to support Ms Gillard and praised her "very strong leadership in very difficult circumstances for the Australian Labor Party."

The week of turmoil for Labor began with disastrous polling showing the party could be left with as few as 40 seats in the Federal Parliament.

Throughout the week a number of Labor MPs ridiculed the party's chances of winning the September 14 election, with one backbench MP comparing Labor to the Titanic.

"It's like the Titanic - we're in the final scenes. Third class has realised the doors are locked and they're not getting out and first class are running around looking for a dress to put on," the MP, a key supporter of Mr Rudd, told ABC News Online.

It was also revealed two long-serving MPs had already packed up their Canberra offices in preparation for the electoral wipe-out.

On Thursday night Mr Rudd was interviewed on the ABC's 7.30 program where he dismissed any suggestion that he was partly to blame for Labor's disastrous polling.

The latest Newspoll results suggest Mr Rudd would be the only Labor MP to retain a seat in Queensland.

On Wednesday long-time Labor MP Laurie Ferguson, who maintains he is a "strong supporter" of the Prime Minister, said Labor was "dead" in critical seats in Western Sydney if Ms Gillard did not engage the electorate on the asylum seeker issue.

Labor going through five stages of grief, Xenophon says

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 12 minutes 6 seconds 12 m Senator Nick Xenophon joins Insiders

Speaking to Insiders, independent Senator Nick Xenophon says a number of Labor members he regards as friends are "simply despondent".

"It's almost, you know, there are the five stages of grief: denial, bargaining, anger, depression and acceptance," he said.

"I think there's going to be a sixth stage that will be written after this election."

Senator Xenophon says he doubts Mr Rudd would be able to change Labor's electoral fortunes if he was elevated to the leadership.

"Some MP said to me if Kevin Rudd came in months ago that he would save a bit of the furniture," he said.

"A few months ago he would have saved the leather lounge suite, right now, I am not sure he would save much more than the beanbags."