The latest Herald DigiPoll survey shows a virtual dead heat in the support between the parties of Government and the parties of Opposition.
National and supporters Act, United Future and the Maori Party have 49.8 per cent support, while Labour combined with the Greens, New Zealand First and Mana have 49.2 per cent.
The poll also shows more than 80 per cent of respondents worrying about the effect of the eurozone debt crisis on the New Zealand economy, with 15.7 per cent very worried.
The gap between the ruling bloc and the rest has been closing since election day, when the difference was 4.2 points. The gap in the last DigiPoll survey in April narrowed to 1.5 points, owing largely to a leap in the fortunes of Labour under David Shearer.
Despite the narrowing gap, the latest party-vote results would give National and support parties a better majority than the seven votes at present on confidence and supply.
While the combined party votes are similar, New Zealand First polled under the 5 per cent threshold, and under the current MMP rules would not have any seats.
But a small improvement in the fortunes of New Zealand First, or the Conservatives if it took votes from National, could easily tip results the other way to a Labour-led Government. Possible changes to the MMP threshhold (at present 5 per cent or one electorate seat) before the 2014 election could also impact on outcomes.
National's support has dropped only 0.6 per cent since April, despite going through a firestorm over increasing class sizes and a subsequent backdown, and the passage of unpopular legislation on partial asset sales.
National is on 47.5 per cent (down 0.6); Labour 34 per cent ( up 0.8); the Greens 9.1 (down 0.2); New Zealand First 4.4 (down 0.5); Mana 1.7 (up 1.6); Maori Party 1.3 (down 0.4); United Future 0.5 (down 0.2); and Act 0.5 (up 0.5).
Non-parliamentary parties, the Conservatives and Legalise Cannabis, both received 0.5 per cent of decided voters. Undecided voters were 8.4 per cent.
On the assumption that Act, United Future, the Maori Party and Mana kept their electorate seats, National would have 60 seats, Labour 43, the Greens 11, the Maori Party 3, Mana 2, United Future 1 and Act 1.
National and support parties would have 65 seats compared with 55 for Labour and potential support parties over the 5 per cent threshold or those with an electorate.
There is little change in the number of voters who think the Government is moving in the right direction: 49.7 per cent compared to 49.2 per cent in April.
And there is little change in the preferred Prime Minister stakes, with encumbent John Key polling 63.5 per cent (63.9 per cent last time) and Labour leader David Shearer on 14.2 per cent (13.1 last time). New Zealand First's Winston Peters is on 7.3 per cent (from 6.4) and the Greens' Russel Norman on 2.7 (from 1.5).
A breakdown of the party vote suggests a gender bias, with National being disproportionately favoured by men and Labour disproportionately favoured by women.
While National's overall rating was 47.5 per cent, it was supported by 51.6 per cent of men and 44.4 per cent of women.
While Labour's overall rating was 34 per cent, it was supported by 28.1 per cent of men and 40.2 per cent of women.
The poll of 750 eligible voters was conducted between June 18 and June 25 and has a margin of error of plus or minus 3.6 per cent. Party vote results are of decided voters only - undecided voters were 8.4 per cent.