LABOR has swept to power in Western Australia with Premier elect Mark McGowan saying it was a victory of "decency and intelligence" over "stupidity and ignorance".
The ALP has ousted the Coalition and longstanding Premier Colin Barnett in a landslide.
One Nation has not had the breakthrough many expected it to but they may still win one to two upper house seats. Ms Hanson remains defiant saying the party has done "extremely well".
Sky's David Speers said it was a "bloodbath result" for the Liberals and "a disaster" for One Nation.
As of 3am Perth time (6am AEST) Labor had taken 36 seats, the Liberals 11 and the Nationals 5. Labor's share of the vote is 42.8 per cent, the Liberals are on 31.4 per cent, Greens 8.5 per cent, the Nationals on 5.4 per cent and One Nation on 4.7 per cent.
'STUPIDITY AND IGNORANCE' - MCGOWAN
At 9.30pm Perth time (12.30am AEST), Mr McGowan went onto the stage at the Labor election function and thanked Mr Barnett for his "loyal service to the state".
He went onto say he loved the people of WA.
"I came here 27 years ago in my Corolla across the Nullarbor and today the people of Western Australia made me Premier. Thank you."
Mr McGowan said the victory was one of "hope and opportunity over desperation and division."
"We are a state of decency and intelligence, not a state of stupidity and ignorance."
He committed to not sell of electricity provider Western Power which became a key election issue.
'THE OVERWHELMING FACTOR WAS TIME' - BARNETT
Around 9pm, Mr Barnett faced Liberal party supporters telling them voter fatigue of the Coalition being in power for more than eight years was the key reason that robbed them off the election.
"The overwhelming factor was time," he said. "Maybe it wasn't good enough but I gave it my best shot in every sense.
"I want to say thank you to the people of Western Australia, than you for allowing me the opportunity opf being Premier."
The result could be expected to be a bitter blow for Ms Hanson who scored a coup when the Liberals decided to preference her party. But it didn't work and on Saturday she said the deal may actually have "done some damage."
But she was all smiles on Saturday night and said the party still expected to gain seats in the upper house. It was a remarkable effort for the party, she insisted, to go from having very little presence in the state to scoring around 6 per cent of the vote.
"To stand that number of candidates as we headed to the polls, I think we are doing extremely well. It's a real start for One Nation (in WA)."
Earlier on Saturday, she said the preference deal with the Liberals had done One Nation "some damage."
Asked by Sky's David Speers if she would do a similar deal at other elections, Ms Hanson said "we're not going to rule it in or out".
Ms Hanson also confirmed the party had banned the ABC from the party's election night bash.
"It's not the first time and it won't be the last," she said. Channel 7 had been allowed into the event and other cameras were taking the feed from them she insisted so she could spend more time with her supporters.
"It's just to give me and the party a fair go."
ONE NATION-LIBERAL DEAL
On the surface, this was a local battle between the Liberals and Labor. About whether the former would remain in power for a third term or the latter will pull the rug from under them.
But it was about much more than that and that's why it mattered to the rest of Australia.
WA's state election was held up as a referendum on Pauline Hanson's One Nation party and if the major parties should shun or embrace her.
And the result is not great for One Nation. Neither are they for the Liberals that effectively got into bed with Hanson angering the Nationals.
The vote is being held against a background of the state's declining economy as the mining boom ends and possible fatigue with the same party holding power for so long.
According to a Nine/Galaxy exit poll, on primary votes the ALP was on 41 per cent up 7.9 per cent from the 2013 election, while the Liberal party has slumped 14.1 per cent to 33 per cent.
And One Nation? Ms Hanson had predicted they'd get five seats, two in the lower house and three in the upper house.
But the poll, which looks like it was a relatively accurate reflection of the eventual result, shows it will get just six per cent of the vote.
It looks unlikely that One Nation will pick up any seats despite a high profile assault on the electorate.
On Saturday, Ms Hanson conceded that the controversial preference deal struck with the Liberals had not gone to plan.
"I think it's actually done One Nation some damage because it's been the biggest topic for people asking about it," she told reporters.
"People ask me about preferences and they don't understand the voting system, the preference system, and the preferences.
"I think that's where most of the damage has come from," she said.
The election has been massively overshadowed by the deal Mr Barnett struck with One Nation.
Although the Premier publicly supported the arrangement to get members of Ms Hanson's party in the WA parliament, he's been visibly frustrated whenever he's asked about his unlikely ally, and has tried to distance himself from the controversial leader.
While things had been looking good for One Nation, the Queensland Senator's presence in the state has been causing more harm than good.
She has faced accusations of sexism from some dumped candidates, supporters have been thin on the ground and the party looked out of touch when they managed to misspell the town of Kalgoorlie on campaign materials.
Senator Hanson defended the One Nation showing, saying the party had only been registered in WA for three months and was fielding 50 candidates.
Meanwhile, the Nationals Brendon Grylls, who could have expected to be the Liberal's closet ally, headed to the polls in a furious mood. Tensions between the partners are close to boiling point not just because of the One Nation deal but also a plan to cut funds meant to be spent in regional areas.
Outwardly, Mr Barnett was being optimistic, noting that around one in five voters were only making up their mind as they turned up to polling booths. "I don't brace for a loss, I always prepare for a win," he told reporters after voting in his seat of Cottesloe.
Labor needs a swing of at least 10 per cent to pick up extra 10 seats to form government for the first time since 2008, which Mr McGowan has said is akin to "climbing Mt Everest".
A Newspoll in The Weekend Australian and the ReachTEL poll in the Weekend West Australian showed that the swing could be even greater and Labor could pick up 14 extra seats.
The Liberal party currently has 30 seats, Labor 21, the Nationals seven and one independent Liberal who defected from the Liberal party. If the polls are right, Labor will have a comfortable majority with 35 seats.
Despite the stunning polls, Mr McGowan was maintaining his cautious outlook. "It's now up to the voters, but I certainly hope this evening we see a change of government because I think that's what Western Australia needs," he told reporters while voting with his family in Rockingham.
He said his team had done their "absolute best to present a good alternative to the people of Western Australia".
Federal Opposition Leader Bill Shorten has joined Mr McGowan on election day, in a sign that Labor is confident of winning.
He said Mr McGowan deserved to win because he had the policies, worked hard and was not arrogant.
"I know that West Australians need something better than what they've had and in Mark McGowan they'll get that outcome if they vote for him today," Mr Shorten said.
Support for Pauline Hanson's One Nation looks to have plummeted in the wake of five candidates either being dumped or quitting, and a controversial preference- swap deal with the Liberals.
One Nation's primary vote has dropped from 13 per cent to 8 per cent in just six weeks.
Mr Shorten said the deal "has been the ultimate exploding cigar of this election campaign".
More than 180,000 early votes and 167,500 postal vote applications had been received by Friday morning.
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