OTTAWA — Deepening economic fear and frayed nerves on the stock market have been steadily carving away at Prime Minister Stephen Harper's electoral hopes, a new poll suggests.

The latest Canadian Press Harris-Decima poll gave Harper's Conservatives 31 per cent support across Canada, just four percentage points clear of the resurgent Liberals.

The New Democrats had 20 per cent support, with the Greens at 12 and the Bloc Quebecois at eight per cent.

Four of every 10 respondents -- particularly women, city-dwellers and older, affluent voters -- say the roller-coaster markets are causing them to rethink their vote, largely at the expense of the Tories, said Harris-Decima president Bruce Anderson.

"The effect of the market, the Conservative response, and the campaigns of other parties are all factors to watch as the final days of this campaign tick down, and the battle appears to be coming down to Ontario," Anderson said.

In Ontario, home to more than a third of the seats in the House of Commons, the Liberals were at 34 per cent, well ahead of the Conservatives at 26 per cent.

Jack Layton's New Democrats were sitting just two points back at 24 per cent, with the Greens at 15 per cent.

"The numbers show little doubt that the Liberals have been having better success, the Conservative campaign has taken a serious hit, while the NDP remains an important wild card, with the prospects of either a breakthrough or yet another polarization slump both plausible outcomes for them."

In Quebec, the Bloc Quebecois stood at 36 per cent, with the Liberals at 28 per cent and the Conservatives at 21 per cent. The poll gave the NDP 10 per cent in Quebec and the Greens five per cent.

Wednesday's poll also suggested newfound support for Liberal Leader Stephane Dion, who is "marginally more popular" than Harper for the first time in the campaign, Anderson noted.

Positive impressions of Dion stood at 41 per cent, with 49 per cent of respondents reporting the opposite. Some 51 per cent of respondents said they had a negative impression of Harper, while 40 per cent were positive.

The rolling sample represents 1,278 interviews conducted Saturday through Tuesday and is considered accurate to within plus or minus 2.7 percentage points, 19 times out of 20.

Because of the smaller sample size, the margin of error for demographic or regional breakdowns is significantly larger.

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 to be held tomorrow, whom do you think you would be voting for in your area?"

On the question of leadership, respondents were asked: "How favourable is your impression of (each leader): very favourable, favourable, unfavourable or very unfavourable?"