The race in Ontario's battlegrounds has tightened up, but the Conservatives still hold leads in the 905 and 519 areas, a new poll has found.

"The erosion of the Conservative vote has been pretty precipitous," pollster Peter Donolo of The Strategic Counsel told ctvtoronto.ca on Wednesday. "They have to pull out of this tailspin somehow."

But "the Liberals are stymied by the NDP and the Green vote," he said.

"The Liberals really need to push that NDP vote down," Donolo said, adding it's not enough for the Liberals to hold the seats they won in 2006.

Liberal Leader Stephane Dion "needs to keep making the appeal by saying 'if you've got Harper on the run, don't let him off the hook by voting NDP,'" he said.

Polling conducted between Oct. 5-7 by the Strategic Counsel for CTV and the Globe and Mail found the following for Ontario's 20 closest ridings from the 2006 election (percentage point change from 2006 in brackets):

• Conservatives - 35 per cent (-2)
• Liberals - 31 per cent (-8)
• NDP - 24 per cent (+5)
• Greens - 10 per cent (+5)

The sample size is 420 and the margin of error is plus or minus 4.8 percentage points, 19 times out of 20.

A week ago, the Conservatives led the Liberals by a 19-point margin in those 20 ridings.

New fears about the economy, compounded by sharp drops in the stock market, have been seen as hurting Conservative Leader Stephen Harper.

But in the 905 ridings, the Tories still appear well-positioned, based on tracking polling conducted on Oct. 1-7 (percentage point change from 2006 in brackets):

• Conservatives - 39 per cent (same)
• Liberals - 35 per cent (-5)
• NDP - 18 per cent (+2)
• Greens - 8 per cent (+3)

The sample size is 215 and the margin of error is plus or minus 6.7 percentage points, 19 times out of 20.

Four of Ontario's battleground ridings are in the GTA's 905 area -- Oakville, Burlington, Mississauga South and Halton. The Conservatives won Burlington and Halton, and came close in the other two in 2006. There are two other 905 ridings -- St. Catharines (Tory in 2006) and Hamilton East-Stoney Creek (NDP in 2006).

In the 519 area, the Liberals are much further behind (percentage point change from 2006 in brackets):

• Conservatives - 41 per cent (+5)
• Liberals - 23 per cent (-14)
• NDP - 24 per cent (+2)
• Greens - 12 per cent (+8)

The sample size is 174 and the margin of error is plus or minus 7.4 percentage points, 19 times out of 20. The polling was conducted from Oct. 1-7.

In the other Ontario battleground ridings in eastern and northern Ontario, the Tories also lead (percentage point change from 2006 in brackets):

• Conservatives - 34 per cent (-4)
• Liberals - 29 per cent (-6)
• NDP 24 per cent (+2)
• Greens - 13 per cent (+8)

The sample size is 309 and the margin of error is plus or minus 5.6 percentage points, 19 times out of 20. The polling was conducted from Oct. 1-7.

Nationally, the Harris-Decima poll conducted for The Canadian Press and released Wednesday has the Tories with a narrow lead over the Liberals (percentage point change from 2006 in brackets):

• Conservatives - 31 per cent (-5)
• Liberals - 27 per cent (-3)
• NDP  20 per cent (+2.5)
• Greens - 12 per cent (+7.5)             

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

With files from The Canadian Press

The 20 Ontario battleground ridings (party holding at dissolution)

905 Ridings: St. Catharines (C), Hamilton East-Stoney Creek (NDP), Oakville (L), Halton (L), Burlington (C), Mississauga South (L).

519 Ridings: Brant (L), Huron-Bruce (L), London-Fanshawe (NDP), London West (L), Kitchener-Conestoga (C).

Rest of Ontario: Parry Sound-Muskoka (C), Glengarry-Prescott-Russell (C), Thunder Bay-Superior North (C), Thunder Bay-Rainy River (L), Ottawa-Orléans (C), Simcoe North (C), Barrie (C), Peterborough (C), Algoma-Manitoulin-Kapuskasing (L).