The new poll shows National with 48.1 per cent support (down 2.8 points), Labour 34.8 (up 6.8), the Greens 9.2 per cent (down 2.6), NZ First 4.9 per cent (down 0.3), the Maori Party 1.7 per cent (up 1.3), United Future 0.7 per cent (up from 0), Mana 0.1 (down 0.2), the Conservatives 0.1 per cent (down 1.2) and Act on zero (down from 1.8).
The result will boost the morale of Labour MPs and party activists at an important time for leader David Shearer, who took over from Phil Goff in December.
Signs of tensions have been emerging in the party over Mr Shearer's moderate style and his failure - until now - to substantially lift Labour's fortunes.
Labour's lift follows a series of political headaches which the Government has struggled to manage.
They include restructuring of the Ministry of Foreign Affairs and Trade, approving the sale of the Crafar farms to Shanghai Pengxin, the resignation of Nick Smith from the Cabinet over a conflict of interest, the decision to veto the paid parental leave bill, and negotiations with SkyCity over increasing its gaming tables and poker machines in return for it building a national convention centre.
Polling was done over 10 days, and only the last two days coincided with the latest political furore, over Act leader John Banks' campaign donations from Kim Dotcom.
The poll suggests voter confidence in the way the country is being run is waning - 49.2 per cent of those polled believe the Government is moving in the right direction (down from 54.4) and 42.1 think it is not (up from 36.7).
Although his support has slipped, John Key is still well in front as preferred Prime Minister, with 63.9 per cent support (down from 66.3).
Mr Shearer has polled 13.1 per cent in his first outing in a DigiPoll survey - down on Mr Goff's rating of 19.5 in the last week of the election but higher than Mr Goff when he got the leader's job after the 2008 election.
New Zealand First leader Winston Peters was third with 6.4 per cent.
The poll of 750 voters was conducted from April 19 to 29. The party vote results are of decided voters only. Of those polled, 7.1 per cent were undecided. The margin of error is 3.6 per cent.