The Ottawa River is emerging as a political dividing line between the Conservatives' and their opponents' fortunes in the upcoming federal election, according to poll results released Wednesday morning.

The poll from Nanos Research showed that while the Conservatives are leading in Ontario, the Prairies and in British Columbia, they are trailing in Quebec and remain statistically tied with the Liberals in Atlantic Canada.

Nationally, the Conservatives have the support of 39.1 per cent of those polled -- a lead of about 11 per cent over the Liberals, with 28.4 per cent.

The NDP follows with 19.8 per cent support, then the Bloc Quebecois with 7.7 per cent and the Green Party with 3.9 per cent.

Regionally, the polling conducted on behalf of CTV and the Globe and Mail is beginning to reveal an east-west trend along party lines, said pollster Nik Nanos.

The Conservatives hold a strong lead in B.C., with 41.8 per cent support -- an increase of five points from polling done a day earlier. The Liberals follow with 25.9 per cent support and the NDP at 24.7 per cent.

The Conservatives enjoy their strongest lead in the Prairies, where they hold 55.3 per cent support compared to the Liberals in distant second place with 24 per cent.

In Ontario the dynamic begins to change. The Conservatives still lead with 44.9 per cent, followed by the Liberals at 36.9 per cent, and the NDP with 12.7 per cent.

East of the Ottawa River, in Quebec, the Bloc holds a significant lead with 32.5 per cent of the vote, followed by the NDP at 25.4 per cent, the Liberals at 20.9 per cent and with the Conservatives trailing with 16.6 per cent.

In Atlantic Canada, the Conservatives and Liberals are in a statistical tie with 38.2 per cent and 34 per cent support, respectively. The NDP has 25.5 per cent support in Atlantic Canada -- its strongest showing in any of the regions.

The new poll also showed that party policy continues to be the key factor, with 52.2 per cent of those surveyed saying it was their top concern when casting a ballot.

In total 21.7 per cent surveyed said the party leader was most likely to affect their vote, while 14.5 per cent listed the local candidate and 8 per cent said they would vote along traditional party lines.

Methodology: A national random telephone survey is conducted nightly by Nanos Research throughout the campaign. Each evening a new group of 400 eligible voters are interviewed. The daily tracking figures are based on a three-day rolling sample comprised of 1,200 interviews. To update the tracking a new day of interviewing is added and the oldest day dropped. The margin of error for a survey of 1,200 respondents is plus-minus 2.8%, 19 times out of 20.