One Nation leader Pauline Hanson Credit:Lisa Maree Williams When the WA campaign began One Nation was polling at just over 13 per cent. The slump since then appears to have been inflicted by the quality of its local candidates, some of whom have proved to be "fruitcakes" said Dr Drum. "When they are in the headlines, it is normally for the wrong reasons." Dr Drum noted that polling throughout the campaign has shown discontent with both major parties, with Liberal losses not all flowing to Labor. He said given that One Nation failed to find enough candidates to run in all the state's contestable seats – and because some candidates appear not to have been closely vetted – the scope of its impact in this environment was unpredictable. In January an article that the party's candidate for the crucial seat of Pilbara, David Archibald, held by the National Party's leader Brendon Grylls, wrote in the musty conservative journal Quadrant was dusted off and republished to a broad audience.

One Nation leader Pauline Hanson on the set of Insiders, watching host Barrie Cassidy. Credit:Meredith O'Shea Listing lifestyle choices that the government should defund, he began with "ugly" single mothers. "The first that springs to mind is single motherhood," Mr Archibald wrote. Premier Colin Barnett on the campaign trail. Credit:Trevor Collens "These are women too lazy to attract and hold a mate, undoing the work of possibly 3 million years of evolutionary pressure.

"This will result in a rapid rise in the portion of the population that is lazy and ugly." Mark McGowan will try to remove Lisa Scaffidi if SAT doesn't. Credit:Alex Ellinghausen On Friday One Nation's candidate for another crucial seat, Kalamunda, on the eastern fringe of Perth, suddenly quit, citing a preference deal between One Nation and the Liberal Party. "I've had enough," Ray Gould, told ABC radio. "I'm talking to voters and they say, 'We like Pauline Hanson but she's done a deal with the Liberals and she can't be trusted'.

"I don't think I'll even get 4 per cent of the vote because she's messing with the voters' heads." Kalamunda could help decide which party wins government. It is held by the Liberal Party with a margin of 10.3 per cent, which is almost exactly the size of the swing Labor needs to win government and, according to recent polling, just about the size of the swing that polling suggests we might see on election day. The Liberal Party has faced criticism for cutting a deal with One Nation that will see it giving preferences to the insurgent outlier in the upper house in return for One Nation's preferences in the lower house. Speaking on ABC TV on Sunday morning, during an interview in which she backed a cut to weekend penalty rates, voiced her support for the Russian President Vladimir Putin and cast doubt on the safety of vaccines, Ms Hanson was frank in support of the agreement. "I have no problem with saying that because it is our best chance of getting One Nation candidates selected to the floor of Parliament. Of course, who is not going to do it?"

The deal has increased tensions between the Liberal Party and its National Party coalition partners, and demonstrated how seriously the Liberal Party takes the One Nation threat. Some observers believe Mr Barnett has effectively sacrificed the lower house seat of Perth, where voters have expressed anger at the deal, in order to stave off One Nation challenges in rural and regional seats. In the aftermath of a mining boom that some analysts consider to have been wasted, the election is being fought over bread and butter economic issues such as unemployment and debt. This has pitted the state's giant resources and agricultural sectors against one another, in turn increasing tension between the coalition partners. The National Party under Mr Grylls is pushing to increase a state production tax on iron ore from 25 cents a tonne to $5, a proposal being fought by WA's Chamber of Minerals and Energy. The Chamber's chief executive, Reg Howard-Smith, has been watching the electorate closely in the lead-up to the election.

"We've been close to the ground over the last few months and the feedback we've got is that everyone is concerned about jobs," he said. "Resource sector jobs, but jobs more generally always comes at the top of the order." Although the tax increase would generate an extra $3 billion in revenue for state coffers, Rio Tinto and BHP Billiton have argued it would cost jobs in the Pilbara and across WA. Mr Howard-Smith also believes the tax rise, which would require legislation to overhaul state agreements with the two companies, would damage the investment attractiveness of the state. "We've had fantastic support across the sector for this campaign we're running about iron ore and that's focused on two companies, but the reason is there are many, many people who can remember the RSPT [Resource Super Profits Tax]," he said.

"When the RSPT was announced, on that Saturday the Dockers and the Eagles were to play – I never got to that game – capital dried up instantly." But Mr Howard-Smith was also concerned about a Nationals plan to give companies payroll tax breaks for workers in the Pilbara who were not fly-in, fly-out (FIFO), an idea which could cost jobs everywhere but in Mr Grylls' own electorate. Mr Howard-Smith said the plan would devastate small towns in the south-west like Busselton and Manjimup where many FIFO workers choose to live, and where the Liberal Party holds a swathe of crucial seats. "If you're coming out of Busselton and you've made the choice to live there but to maintain your job you have to travel to the Pilbara, then it's clearly a matter of choice," he said. "Manjimup only has a small number of FIFO workers, in the twenties, but by the time you look at families and everything else, the contribution they make is significant.

"Rio reached out to those workers in Manjimup. At the time the timber industry was closing there were some good operators who they took on, so it just doesn't make any sense. "They would have the most mature FIFO model, so you have a lot of people coming out of Busselton, a number from Albany, Geraldton, and Broome and Broome is essentially Aboriginal employment. "That's working extremely well and I don't think the National party policy is realistic for one moment." Unions have been quick to link the Liberal Party to One Nation. On Sunday the Victorian CFMEU leader John Setka tweeted in reference to the penalty rates decision, "Pauline Hanson is just another Liberal who hates workers!" Ms Hanson herself travelled to Western Australia to begin a week's campaigning on Sunday, with an itinerary planned to include stops in Perth and towns in the south-west as well as regional centres including Port Hedland, Karratha, Kalgoorlie and Geraldton.

The Labor leader Bill Shorten is expected to join the campaign later in the week. So far the Prime Minister, Malcolm Turnbull, whose last WA visit was not warmly received, has no plans to make the trip. WA Number Crunching To win government, Labor's Mark McGowan must win 10 seats from the Liberal Party's Colin Barnett, a swing of 10 per cent across the board. Last week's Fairfax ReachTEL polling puts Labor 4 points ahead on a two-party-preferred basis.

Opinion polling has Pauline Hanson's One Nation as high as 10 per cent on its primary vote.

Barnett's Liberals will be preferenced by Hanson's One Nation in a controversial deal that could deliver him government and One Nation the balance of power in the state's upper house.

In 2001, Labor won government on the back of One Nation preferences after Liberal Premier Richard Court refused a preference deal with Hanson's party.

The traditionally fraught relationship between the Liberals and the Nationals has been strained by the One Nation preference deal and a plan by the Nationals leader Brendon Grylls to increase tax on WA's iron ore companies.

Nationals leader Brendon Grylls is under threat in his Pilbara electorate from a resurgent One Nation and the risk his proposed mining tax poses to jobs in the regions.

Pundits find it remarkable the primary votes of both major parties are below 35 per cent and describe the result as "unpredictable".