However, University of Otago political scientist Bryce Edwards says the polls reinforce each other and Labour is picking up an unfortunate narrative as being a loser in September's election.
Yesterday's Stuff.co.nz/Ipsos poll and Wednesday's Roy Morgan poll had a yawning gap between support for National and Labour, at 30 percentage points (54.8% versus 24.9%) and 27.5 percentage points (51% and 23.5%), respectively.
As preferred prime minister, Mr Cunliffe drew only 12.8% support in yesterday's poll, well behind Prime Minister John Key's 53.7%.
In Queenstown yesterday, where he has been holidaying with family, Mr Cunliffe told the Otago Daily Times the polls were not what Labour would like to see and it had more work to do.
''Having said that, of course, they are a point in time and it is the election date itself that is the most crucial.
''We will be going all out to muster every possible vote and we can still win this election.''
The party did not necessarily have to change its message. The key to attract marginal voters was message consistency, he said.
''You'll see more from us which will, I think, resonate with the public about being here for middle-income Kiwis and more vulnerable Kiwis.''
Dr Edwards said the demoralising polls might have Labour's support in the mid-20s but a win for the Left bloc, including the Green Party, was not impossible.
''The problem is it [the poor polling] creates a narrative of Labour being losers in this election.''
Undecided voters are looming as an important factor in the election. The Stuff/Ipsos poll said more than 15% of people were unsure of which party they will support.
Labour gained 1.7 points to 24.9% after a series of education-related announcements.
Mr Cunliffe said Labour expected that shift to continue as it targeted areas with traditionally high Labour voter turnout and policy which would appeal nationally.
He latched on to a dip in Fonterra's latest Global Dairy Trade auction as a sign the economy - seen as a Government strength - was turning sour. Labour would focus on the stagnating regions to try to break the Government's good-news messages about the economy, he said. Median incomes in 13 of the country's 16 regions had gone backwards since National took office in 2009.
Mr Cunliffe met Queenstown Lakes Mayor Vanessa van Uden yesterday to discuss housing and other local issues.
