John Howard will enter the final week of the election campaign well behind his rival, after a new poll of the government's most marginal seats showed the coalition has failed to gain ground on Labor. 

On a two-party-preferred basis, the coalition slipped one percentage point to 46 per cent, the Newspoll in The Australian newspaper shows. The coalition now trails Labor by eight points. 

The survey of the coalition's 18 most marginal seats in NSW, Victoria, Queensland and South Australia is the largest Newspoll published during the election campaign. More than 3,600 voters were interviewed between Monday and Thursday. 

If the swing recorded in the survey is uniform in the marginal seats and across the board in the four states, the coalition will lose between 18 and 25 seats, include Mr Howard's seat of Bennelong, The Australian said. 

Coalition Falls Further Behind: Newspoll