Australia’s two major parties are neck-and-neck as voters prepare to go to the polls on Saturday, after a bruising election campaign that has turned personal, prompted the issue of climate change to come to the fore, and led to the campaigning of the Murdoch press almost backfiring.

Up for re-election is the incumbent centre-right Coalition government, led by the prime minister, Scott Morrison, leader of the Liberal party. The Coalition is bitterly divided over climate change and suffering after years of factional infighting. It has held power since 2013 but has been behind the opposition Labor party in the polls since mid-2016.

Climate change takes centre stage in Australia's election Read more

However, Labor’s lead has narrowed through the five-week election campaign, with the latest Guardian Essential poll putting Labor ahead of the Coalition just 51.5% to 48.5%.

The difference between the offerings of the two parties ahead of the poll has been stark, with Labor laying out a suite of policies including controversial tax reforms targeting the “top end of town”, which it says will reduce inequality and fund health, education and environmental programmes.

In setting out its plans, Labor has made itself a “big target” for the Coalition, whose strategy throughout the campaign has been to attack Labor’s policies, rather than to propose many of its own, beyond a proposal to cut business and personal taxes.

Facebook Twitter Pinterest A busy pre-polling booth in the Queensland electorate of Lilley. Photograph: Mike Bowers/The Guardian

This was seen most starkly in the final leaders’ debate when the leaders were allowed to ask each other questions. The Labor leader, Bill Shorten, and Morrison asked each other two questions about Labor policies.

“And that,” wrote Greg Jericho, Guardian Australia’s economics columnist, “is the election campaign boiled down to its essence”.

Morrison, a former treasurer, took over as prime minister in 2018 after toppling Malcolm Turnbull, his more moderate predecessor. Turnbull took the prime ministership from his Liberal party rival Tony Abbott in 2015.

His campaign has largely been a one-man show, with his ministers conspicuously absent from public appearances, in part because he leads a decidedly divisive party, after last year’s leadership coup and also partly because Morrison’s strategy has been to try and frame this election as a popularity contest between himself and Shorten, a former union leader who has had consistently poor personal approval ratings.

Facebook Twitter Pinterest Scott Morrison, who took over from Malcolm Turnbull as PM last year. Photograph: Mike Bowers/The Guardian

The Coalition’s hope is that voters’ dislike of Shorten is strong enough to cause them to forget how savagely Morrison’s party has torn itself apart in recent years and its lack of vision, particularly on climate change, which has become one of the most significant issues in the campaign.

Labor has committed to a target of reducing emissions by 45% by 2030, and says the difference between the two parties’ policies on climate change is “perhaps above all others … night and day, black and white”.

The Coalition – or “COALition” as they have been dubbed in attack ads – are pushing for a “climate solutions” fund that pays polluters to lower their emissions, but experts question whether this will achieve’s Australia’s commitment under the Paris agreement to lower emissions by 28%. The Coalition has also said it would support new coal mines and, just two days before the election was called, pushed through environmental approvals needed to progress the controversial Adani coal mine project near the Great Barrier Reef.

Tabloid feels sting in its tale

At moments it has been a bruising, personal campaign, the nadir of which came as the Murdoch-owned, Sydney-based tabloid the Daily Telegraph used Shorten’s deceased mother as a grounds to attack the Labor leader.

In response, Shorten, who defied convention at the beginning of the campaign by being the first Australian party leader in decades not to travel to New York to meet Murdoch ahead of an election campaign, gave a tearful press conference in which he called the article “bloody lazy” and “gotcha shit”.

The story, which was published in the week leading up to Australian Mother’s Day, backfired spectacularly, prompting widespread criticism, including from the prime minister. Australians began posting stories about their own mothers under the hashtags #MyMum and #BillsMum.

Shorten’s personal approval rating jumped four points in the week following the story.

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Things also got personal for the prime minister, who was asked whether he, as a Christian, thought gay people go to hell because of their sexual orientation. The question was prompted by the case of Israel Folau, the star Australian rugby player, who has been suspended from the Wallabies for posting on social media that “hell awaits” for homosexual people.

After initially dodging the question, Morrison eventually confirmed he did not believe homosexuality was grounds for damnation and criticised Shorten for bringing religion into the debate, saying he was “not running for pope, I’m running for prime minister”.

A factor in Saturday’s result will be the rise of a number of high-profile independent candidates, many of whom have positioned themselves as climate-concerned protest candidates and who are running against prominent government figures such as former prime minister Tony Abbott and federal treasurer Josh Frydenberg.

Another player in the game is Clive Palmer, a highly eccentric billionaire mining magnate, who has spent a fortune on an advertising blitz for his United Australia Party. The Liberal party has been criticised for entering into a deal for preferences – due to Australia’s preferential voting system – with Palmer, who was elected as a member of parliament in 2013 and is hoping to win a Senate seat this time around.

Complicating matters somewhat, the Liberal party announced in 2016 it would “use every power at its disposal” to investigate a collapsed business of Palmer’s, so if Morrison wins on Saturday and Palmer picks up a Senate spot, the government will be in the tricky situation of needing to court a senator whom it is also investigating.

With the finish line in sight, the party leaders are making final dashes across the country to convince voters in the few dozen marginal seats that will determine Saturday night’s result.

Despite the fact Labor has been ahead of the Coalition in every poll for three years, analysts warn the result is not a foregone conclusion, anticipating different results in different parts of the country rather than a uniform national swing for or against the government, making the final result difficult to predict.