Labor has gained ground in the final week of the campaign but the Coalition remains set to win Saturday’s election with 50.8% of the two party preferred vote to Labor’s 49.2%.

A Guardian Lonergan mobile-only poll, taken primarily on Thursday night as the Coalition finally released its policy costings and was forced to backflip on its originally-released internet-filter policy, showed a higher vote for the Greens and “others” flowing through to the Labor party’s two party preferred vote after the distribution of preferences.

The poll of 862 voters found the Coalition’s primary vote had fallen from its early campaign high to 42%, the Labor party’s rising slightly to 34%, a rise in the Greens’ House of Representatives vote to 14% and “others” to 10%.

The poll indicated a potentially higher vote for the Greens (at 16%) in the Senate, where “others” polled at 8%, Labor at 29% and the Coalition at 40%.

Lonergan research chief executive Chris Lonergan cautioned that in previous elections “the actual Senate vote has tended to differ from the self-reported voting intention figures in polling, possibly because it is very difficult to convey the complexity of a Senate voting form over the telephone”.

But he said based on these poll results he expected to see a strong result for the Greens and the minor parties in the Senate.

The poll shows a slightly better lower house result for Labor in two party preferred terms than three other final-week polls already released, largely due to the higher recorded primary vote for the Greens. Both Galaxy and Reachtel polls showed the Coalition leading 53% to 47% in two party preferred terms and an Essential poll showed the Coalition with a 52% to 48% lead.

“The fact that this is a mobile-only poll is very significant,” Lonergan said.

“We know a growing proportion of Australians do not have a landline at all, and many more Australians rarely or never answer a landline call – yet almost all Australians carry a mobile phone. We believe that a mobile-only poll is the most accurate means of measuring the views of Australians in 2013.”

Guardian Lonergan mobile-only poll

The slight narrowing in the Coalition’s lead and the better polling results for the Greens and minor parties comes as Coalition leader Tony Abbott made voting for the Coalition, and not for minor parties, a central theme of his final day’s campaigning.

“I say to people today, please if you don’t want another three years like the last six, you have got to vote for your Liberal candidate – House and Senate – because if you don’t we might get stuck with another bad Labor Green government, Green dominated Senate, and that is the last thing we want … no ifs, no buts, vote for the Liberal party House and Senate,” Abbott said on Friday during a last-minute blizzard of campaign stops and interviews.

In another interview, Abbott said it was like being ahead five minutes from the final hooter in a football grand final and having “these minor parties and independents who are trying to invade the pitch and muck up the way the game concludes”.

Kevin Rudd, who has finished the election campaign strongly after a faltering start, was also on the hustings to the end.

He appealed to undecided voters and repeated his allegation that the Coalition would make big spending cuts, despite the release of its costings on Thursday showing no net cuts to either health or education.

“You know something, we have still got a day before this election happens. What we know is there’s still a large number of undecided people. Your poll says there is a three percentage point gap, well let’s just wait and see.

“I'm pretty confident in the good sense of the Australian people who will make judgments in the future about their schools, their hospitals, whether they will get decent broadband in the future which is affordable, reliable and high-speed, and whether their jobs are secure as well.

“I think these are the big questions, and the other side of the coin is Mr Abbott's massive cuts which he has kept under wraps right until election day. No details out there at all,” Rudd said in one of his many final campaign interviews.

Labor is now focusing its allegations about Coalition cuts to come on Tony Abbott’s planned commission of audit, which Abbott has said will cover all portfolios.

The Greens, meanwhile, were continuing their campaign theme of appealing to voters to take out insurance in the Senate against total Coalition control.

"With polls showing Tony Abbott is likely to be Australia's prime minister, it is essential to Abbott-proof the Senate so that he does not get total control of the parliament," the Greens leader, Senator Christine Milne, said.

Rudd’s last-minute return to the Labor leadership just weeks before calling the election had narrowed Abbott’s polling lead, but over the course of the campaign the Coalition has pulled away to a clear election-winning margin in every published poll.

Apart from the Age and Guardian Australia, all other newspapers editorialised in favour of the Coalition. Guardian Australia’s editorial can be read here.

The Guardian Lonergan poll was taken primarily on 5 September, with some interviews on 4 September, using voice-automated telephone interviewing. The margin of error is 3%.