OTTAWA - The New Democrats and Greens appear to be gaining while Conservative support is slipping in the federal election campaign, a new poll suggests.

Liberal support has been relatively stable during the campaign, with minor fluctuations that are within the margin of error, The Canadian Press Harris-Decima survey suggests.

"There's no question ... the Tories got out of the gate fast and they've been bleeding since then," Harris-Decima president Bruce Anderson said Thursday.

The survey taken over the last four days gave the Tories 36 per cent, down two percentage points from Wednesday's figure, followed by the Liberals with 27, down a single point.

The poll put the NDP at 16 per cent and the Green party at 11, both up a point, while the Bloc remained at eight per cent.

The poll surveys 300 people a night in a national sampling, and the latest figures are based on interviews with 1,366 people Sept. 13-16, with a margin of error of plus or minus 2.6 percentage points, 19 times in 20.

The Tories came roaring out of the gate with 41 per cent of respondents' support at the outset of the campaign -- majority government territory. Anderson says the Greens and NDP appear to be the ones who've benefited from their slide.

"This race continues to become more interesting, and outcomes are becoming more varied and complex," Anderson said.

"Probably no question looms larger in terms of its import for both the Liberals and the Conservatives than the question of vote splitting on the centre-left and, in particular, among younger women."

The survey suggests the race remained tight in Ontario, with the Conservatives at 37 per cent and the Liberals at 34, both down a couple of points, with the NDP at 15 per cent support and the Greens at 12, both up slightly.

All the short-term changes are well within the survey's margin of error, which is higher for regional counts.

The strength of the NDP and the Green party reflect both the biggest risk and the biggest opportunity for the Liberals, Anderson said.

It also means good news for the Tories -- but only to a point.

"One way to interpret the trends is that the Conservatives -- not just the Liberals -- have been failing to attract those voters," Anderson said.

"And what many seemed to feel was a foregone conclusion -- a Conservative win, and potentially a large win -- has become less certain."

The polling suggests positive feelings toward Stephen Harper slid somewhat. Respondents who reported positive impressions of the Tory prime minister were at 47 per cent, down from a peak of 53 per cent in the Sept. 8-11 period.

Negative impressions of Harper climbed to 45 per cent, up from a low of 40.

The poll suggests the Bloc leads in Quebec with 33 per cent, followed by the Conservatives 24, the Liberals with 20, the NDP at 14 and the Greens at eight.

In Atlantic Canada, respondents put the Liberals at 36 per cent, followed by the Conservatives with 28, the NDP with 21 and the Green party with 11.

Among British Columbia respondents, the Conservatives led with 35 per cent, followed by the Liberals with 25, the NDP with 23 and the Greens with 14.

The poll suggests the NDP have gained ground among urban women, especially between the ages of 18 and 34, where the New Democrats had 25 per cent support, an eight-point jump since the writ was dropped.

Because of the smaller sample size, margins of error for regional or demographic results are significantly larger than for the overall percentages.

More information on the poll is available from www.harrisdecima.com. Respondents to the poll were asked the following question: "If a federal election were being held tomorrow, who do you think you would be voting for in your area?"