With only a fortnight to go in the five-week election campaign, the latest Fairfax-Nielsen poll shows Mr Abbott's Liberal-Nationals Coalition extending its lead over Labor, to be 53-47 on a two-party-preferred basis.

It was 52-48 in the same survey in early August, shortly after the election was called.

While both leaders have lost some skin in the campaign, Mr Abbott has retained a 7-point lead as the more trusted leader, with a rating of 43 per cent to Mr Rudd on a career low of 36 per cent.

Labor's primary vote has dropped to 35 per cent compared with the Coalition on 47, with the Greens steady on 10.

On the question of preferred prime minister, Mr Rudd's commanding 14-point lead of 55-41 in July has been reduced to a statistically insignificant 3 points on 48-45.

The clear trend suggests voters across the nation are considering just the seventh switch of a governing party at national level since World War II.

A separate Newspoll, published on Saturday, shows Mr Rudd is at risk of losing his own Brisbane seat in a possible election rout. The Coalition candidate in the Prime Minister's seat of Griffith, Bill Glasson, leads Mr Rudd on a two-party preferred basis by 52 per cent to 48 per cent.

Mr Glasson's primary vote support has surged 12 percentage points since the 2010 election, according to Newspoll.

The Fairfax-Nielsen poll found an overwhelming 70 per cent of voters now believe the Coalition will win on September 7, compared with just 20 per cent who tip Labor to come from behind. Voters have answered that question correctly in the Fairfax-Nielsen poll before every election since 1998.

The poll of 2545 respondents taken between August 18 and 22 surveyed 980 voters in NSW and 972 in Victoria.

In NSW, where Labor had hoped to keep losses to one or two seats in western Sydney, offset by expected gains in Queensland, Labor's primary vote is down to 34 per cent - a drop of some 5 points since the election was called.

On a two-party-preferred basis, Labor's share of the vote in NSW has slumped to 44 per cent to the Coalition's 56, putting a swag of Labor seats in peril including: Greenway (0.9 per cent); Robertson (1 per cent); Lindsay (1.1 per cent); Banks (1.5 per cent); Reid (2.7 per cent); Parramatta (4.4 per cent) and Kingsford-Smith (5.2 per cent).

In the Labor stronghold of Victoria, ALP support has fallen by 4 points since 2010, although that decline is off a very high base of 55.3 per cent.

The result shows Labor's prime-time election advertisements, which warn of the threat of an Abbott government slashing essential services and cutting public spending ''to the bone'', have failed to bite.

Mr Abbott's 53-47 lead represents a swing of 3 per cent since 2010. If carried through to polling day, that would account for the loss of 10 Labor-held seats.

Particularly concerning to Labor is that Mr Rudd has lost ground to Mr Abbott in the head-to-head race of preferred prime minister. Labor's man still leads but the closest Mr Abbott came previously was within 10 points of Mr Rudd just before Labor replaced him with Julia Gillard.

Among the few positives for Labor is the ALP is still more trusted when it comes to providing paid parental leave, despite - or perhaps because of - Mr Abbott's super-generous scheme delivering full wage replacement for high income-earning new mothers for six months after birth.

Pollster John Stirton said the most telling message from the poll was the sense of steady decline in Labor's vote.

''This is just continuing that trend ,'' he said.