Australians have put Labor ahead of the Coalition in the two-party split, as the government prepares to reveal an updated forecast for next year's budget surplus.
Labor has maintained a 54 - 46 lead over the Coalition in a new poll but Prime Minister Scott Morrison remains more personally popular than his rival.
The Fairfax-Ipsos poll released on Monday offered a snapshot of where the two major parties stand going into the Christmas break.
The Morrison government will pitch its economic management in the MYEFO budget update this week, while Labor is hoping to present a united front at its national conference in Adelaide.
On a two-party preferred basis, 54 per cent of those surveyed said they would vote for Labor, up from 52 per cent a month ago, while 46 per cent said they would vote for the Coalition, down from 48 per cent.
Labor's primary vote also rose from 34 to 37 per cent in the month, while the Coalition's dipped by 1 per cent to 36 per cent.
If these numbers were to play out at the next election, due by May, the Coalition could lose at least 18 seats.
Scott Morrison still leads as preferred prime minister, but opposition leader Bill Shorten has narrowed the gap.
The survey of 1,200 Australians has found 46 per cent would rather Mr Morrison be their leader, while 37 per cent preferred Mr Shorten. The nine percentage-point gap is the tightest result on the leadership question in the past two years.
"We are united, we are determined, and we are ready," Mr Shorten told the ALP's national conference in Adelaide.
Labor is likely to adopt a higher intake of refugees and overhaul its environment policy as the right and left factions within the party seek to reach a compromise without damaging public disputes.
The poll also shows Australians aren't overwhelmingly buying Labor's $32 billion plan to trim back negative gearing tax concessions on investment properties.
The reform divided voters with 44 per cent against the policy while 43 per cent were in favour and 13 per cent were unsure.
Additional reporting by AAP.