After days of speculation, Kevin Rudd has confirmed he will take on Julia Gillard at a party room leadership vote on Monday as he tries to make a comeback as prime minister.

He says he wants to finish the job the Australian people elected him to do when they voted for him in 2007.

He spoke of encouragement from many of his colleagues and that how he thinks Monday's vote should be a secret ballot for leadership.

Mr Rudd said the Labor party was "heading for the rocks at the next election".

"That's why I'm here today because I believe that to do the best for Australia and Labor things have to change," he said in Brisbane on Friday.

"It is no secret that our government has a lot of work to do if it is to regain the confidence of the Australian people.

"Rightly or wrongly Julia has lost the trust of the Australian people and starting on Monday I want to start restoring that trust.

"That's why I have decided to contest the leadership of the Australian Labor Party."

Rudd talked about opposition leader Tony Abbott, saying that his 'outdated' ideas reflect the 1950s. He said he has never met a more negative man in Australian politics.

He says Abbott is the single most conservative leader that the Liberal party has ever had.

On the Greens, Rudd said that they can't offer growth like the Labor party can.

Rudd confirmed that if he loses on Monday, he will go to the backbench and won't challenge for leadership again.

At last count, Labor MPs are favouring Prime Minister Gillard at a rate of more than two to one, Fairfax reports.

Ms Gillard has 68 votes and Mr Rudd 29 with three more votes likely to go each of them.

Labor MP Nick Champion has quit his role as secretary of the Federal Parliamentary Labor Party because he wants to speak out in defence of Kevin Rudd.

He says in his resignation letter the tactics which are being used against Kevin Rudd are unacceptable and counterproductive for the party.

Mr Champion is the ALP member for the northern Adelaide electorate of Wakefield.

Another South Australian Labor MP Steve Georganas says the Prime Minister Julia Gillard has his support.

"It's very important that we get this over and done with. I think we have been hurting for a long time we have to sort this once and for all and we'll sort it out on Monday and get on with the job," he said.

Another SA member Amanda Rishworth says she will be supporting Ms Gillard in any ballot.

"I think it's been a bit of a distraction from what our job is to get on and govern. I think people want us to do that we've got a lot of very positive things rolling out in my electorate like the national broadband network," she said.

Employment Participation and Child Care Minister Kate Ellis, the member for Adelaide, is also backing Ms Gillard.

Earlier, Mr Rudd arrived home from the US but would not immediately commit to a challenge.

"I will be making a statement definitively on this later today, after speaking to my colleagues," he told journalists.

He urged voters to contact their local MPs, senators and media to voice their concerns.

"Your power as the people is what will count in the days ahead," Mr Rudd told voters via the media.

"Pick up your telephone, speak to your local members of parliament, tell them what you think, jump into the media, tell them what you think, because this is your country, it doesn't belong top the factions of the Labor party."

Speaking shortly after Mr Rudd gave his press conference, Ms Gillard took a swipe at his call to arms, comparing it to an episode of a reality TV show.

"The choice that my colleagues will make on Monday is about who should be prime minister of this nation," Ms Gillard told reporters in Adelaide.

"It is a choice about who's got the strength, the temperament, the character, the courage, to lead this nation, who's got the ability to get things done even in the face of adversity.

"This is not an episode of Celebrity Big Brother, this is about who should be prime minister."

Ms Gillard said as prime minister she got through big reforms that "languished" under Kevin Rudd.

Speaking shortly after Mr Rudd gave a press conference in Brisbane, Ms Gillard said she had spoken with a "large number" of colleagues over the last 24 hours.

"They are going to come to Monday's caucus meeting exercising their best judgment about who should be prime minister and who should lead this nation for the future," she said.

Earlier in Brisbane, Mr Rudd said the "faceless men" of the Labor party had, in the past few days, used "shock and awe tactics" to launch personal attacks against him.

The former foreign minister said there were also reports of sitting MPs having their preselections threatened.

He said both tactics were similar to those used back in June 2010 when he was rolled by Ms Gillard for the top job.

Mr Rudd said his "challenge" to the prime minister was to provide a public guarantee on Friday "that any sitting member of parliament in the House of Representatives and in the Senate will be guaranteed of their preselection again so that they have that fear removed from them".

He said MPs' preselections had also been threatened in the lead up to the 2010 coup.

"(MPs were told) you either vote for what the faction tells you or we'll knock you out of parliament. That's un-Australian," Mr Rudd said.

Mr Rudd was referring to reports in the media that some MPs' preselection had been threatened if they supported him.

He said that in politics, trust and confidence were everything.

"The core question for members of the Australian parliamentary Labor party, for the Australian people, right now is whether they believe the current prime minister has the trust and confidence of the Australian people," he said.

"If you don't have that, you can't do anything else."

Mr Rudd said the days ahead were important for Australia.

He framed his address around his vision for the nation, versus Opposition leader Tony Abbott's, who he said was buried in a different age.

"For the last 12 months Mr Abbott has been on track to become prime minister of Australia in a landslide," he said.

"It's not just a few days, a few weeks, even a few months.

"The core question for my parliamentary colleagues and I believe for the Australian people, is who is best equipped to defeat Mr Abbott at the upcoming election.

"But more importantly, to prevent him from inflicting his prescription on Australia's future."

Mr Rudd told people not to believe the scathing critiques of him that had been made by senior ministers in recent days that suggested "Kevin Rudd is the anti-Christ incorporated, and if not the son of Satan, at least the grandson of Satan".

"Just have a little pause for thought. I may not quite be like that, there might be a vested interest at play in putting those views forward," he joked with reporters.

There is intense counting behind the scenes to establish Mr Rudd's support base.

Mr Rudd is planning an assault by phone in a bid to stave off defeat in the ballot which will be held at 10am(AEDT) on Monday morning, Fairfax reports.

The 72-hour blitz will also involve visits to key Queensland seats ahead of the release of the latest numbers from Newspoll.

Mr Rudd's supporters admit he faces a difficult task to secure enough votes to win the leadership ballot.

Few members of caucus have been willing to publicly back Mr Rudd, and Julia Gillard's supporters are confident she will retain the leadership decisively unless there is a dramatic development over the weekend.

Ms Gillard wants the poll to settle things once and for all and says if he loses Mr Rudd should move to the backbench and let go of his leadership aspirations.

But some of Mr Rudd's backers say conditions could change in the coming months and they will not rule out another tilt at the leadership later this year if Mr Rudd is not successful.

Meanwhile, MS Gillard says that although she has made mistakes, she believes she can lead Labor to victory in the next federal election.

In an article written for News Ltd today, Ms Gillard has outlined why she is best placed to lead the Labor Party.

"No government is perfect and I have made mistakes over the past 18 months," Ms Gillard said.

"But ultimately the measure of a government is what the government achieves for the Australian people, what meaningful change and meaningful reforms are delivered."

Good government should not be driven by opinion polls or news headlines but should be about pushing through reforms, she said.

"Government is about making sure that each and every day you have the discipline and the method necessary to get the huge volume of work done.

"Government is about having the personal strength in adversity to still ensure that you stay focused and get your job done.

"I believe I have demonstrated those attributes," she said.

"I believe that we can win the next election ... I believe I can lead Labor to that victory."

Ms Gillard pointed to her history as leader, which she said has been marked by securing "major reforms", including the introduction of the Minerals Resource Rent Tax, means testing the private health insurance rebate and the carbon tax.

The comments come after Ms Gillard announced on Thursday she would call a ballot for the Labor Party leadership at 10am on Monday, following Kevin Rudd's resignation.

"In this leadership ballot I will be saying to my colleagues that we need to come together and to keep working in the interests of the Australian people."