Democratic presidential candidate John Kerry would beat President George W Bush by a significant margin if a presidential election were held now, the CNN/USA Today/Gallop poll released on Monday said.
The survey indicated the Massachusetts senator would win 52 per cent of the vote compared to Bush's 44 per cent.
A similar poll in January gave Bush 55 per cent to Kerry's 43 per cent.
In the latest poll, however, most Americans retain confidence in Bush's foreign policy and his handling of security issues, while Kerry is more trusted with the economy, public health and education.
A significant 65 per cent of respondents said they were more likely to base their decision in November on economic issues than on progress made in the war on terror launched after the September 11 attacks on the United States in 2001.
The survey of 1,005 adults was conducted late last week after Bush launched a new television advertising campaign, which caused controversy because it used September 11 images. It had a margin of error of plus or minus three percentage points.