Coalition return to office 'likely': Green

Election expert Antony Green says reduced preference flows to the Labor Party will make a coalition election victory on July 2 "more likely than not".

The ABC psephologist addressed the Australian Business Economists group in Sydney on Tuesday, saying Greens preferences to the Labor Party will decline relative to 2013.

"Greens preferences flowed 83 per cent to Labor last time, much higher than normal," Mr Green said.

"And we've got a completely different composition of the minor parties this time without Clive Palmer."

Recent polling by 7News-ReachTel placed Labor ahead of the coalition 52-48 on a two-party preferred basis.

But Mr Green said these results may mask a great deal of coalition support.

"The coalition has sitting members in some of these marginal seats which is to their advantage, so you'd have to say the coalition is basically better positioned," he said.

"It also has the more popular leader which is something to leverage."

Mr Green, an adjunct professor at Sydney University and expert in voting behaviour and election modelling, said the Liberal Party could suffer a 3.3 per cent swing and still retain office.

Mr Green said the House of Representatives' state of play in NSW, Victoria and Queensland could be best explained via military metaphor.

Victoria was an attritional World War I battle in which "the two sides have fought each other to the trenches", but were unlikely to make large gains, while NSW and Queensland were cavalry charges "on a wide sweeping front".

In Queensland the vote would depend on where former Palmer United Party voters placed their trust, while in NSW electoral redistributions may harm the Liberals.

Elsewhere, Mr Green expected the rise of the Nick Xenophon Team to ruffle feathers in South Australia, where it looks set to capture a number of seats, and for the Liberals to suffer in Western Australia as the resources boom fades.

"The government needs to hang onto seats in NSW, diminish the swing in Queensland and hope for the best in Western Australia if things go wrong in the east," he said.

In the senate, the government "has made life difficult for itself" by going to a double dissolution election and may lose a senate seat in three states, but will gain two seats elsewhere.

Mr Green said the new senate voting system would prevent the election of micro-party candidates like Ricky Muir.

"If a party can get four per cent of the vote, they're in with a chance for that final seat. They can't get it with half a per cent anymore," he said.