OTTAWA - A growing number of Canadians, especially in Quebec, say the rising death toll among troops in Afghanistan is too high a price to pay for helping the troubled country, suggests a new poll.

A Canadian Press-Decima Research survey shows 67 per cent of those asked believe the number of casualties has been unacceptable, a five-percentage-point rise from a poll taken a little over a month ago.

Only 25 per cent of respondents said the number of killed and wounded was acceptable, in a survey taken following the most recent deaths of six soldiers in a roadside bomb attack.

Bruce Anderson, CEO of Decima Research, said Canadians are clearly becoming more doubtful about whether progress is being made, in light of the deaths of 66 soldiers and one diplomat in Afghanistan.

"In the absence of more evidence of progress, and in the wake of still more deaths of Canadian soldiers, it's clear that discomfort with the mission is growing, and people are questioning whether the lives being lost so honourably are being lost in vain," said Anderson.

Of particular concern to the government of Prime Minister Stephen Harper is the result showing skepticism runs highest in Quebec, where 76 per cent said the sacrifice is unacceptable. This comes as the Royal 22nd Regiment - the famed Vandoos - prepare to take over the battle group in Kandahar next month.

"Given the importance of Quebec to the Conservatives in terms of trying to fashion a strong win in the next election campaign, the fact these numbers are deteriorating" should be cause for concern, said Anderson.

Even among the most ardent supporters of the war - people who identify themselves as Conservatives - doubt has crept in. The number of Tories who say the price tag has been too high increased by eight percentage points since the beginning of June, to 48 per cent.

Bloodied by the last 16 months of fighting in the deserts of southern Afghanistan, and with a year and a half left in the country's combat commitment, a respected historian said Canadians are at a crossroads.

"Canadians have to decide whether they want to win," said Desmond Morton, a professor at Montreal's McGill University.

Anderson agreed that the latest deaths could mark a tipping point for Canadian involvement in war-torn region.

"Are we past the point where the confidence level can be restored?" he said.

"If we talk about restoring confidence to the point where Canadians would support an extension of the mission, we may well be past that point. However, circumstances can always change. The problem for Canadians is that they don't believe we can win this conflict."

Harper has repeatedly hinted he may be prepared to end Canada's combat role when the current mission expires in February 2009, but said the question of an extension would be debated by Parliament, likely next year.

Morton says Canada has never lost a war and if Anderson's assessment of the public mind is correct, the country is setting itself up "for its first international humiliation of an unquestioned kind."

Over the last few months, Morton said, he's often wondered whether the public is talking itself into defeat and if Canadians have the stomach to fight the way our parents and grandparents did during two world wars and the Korean conflict.

"It is sad when (casualties) happen," the soldier-turned-historian said in a telephone interview.

"It was sad when it happened in 1944, in 1918 or 1917. In fact, in 1918 we suffered our heaviest casualties of the First World War, by far. Did anybody in Canada notice? No, because we were winning. If you pitch this war as a hopeless war we cannot win and every death is a needless sacrifice."

The Conservative government and the military have often accused the media of placing more emphasis on casualties than accomplishments in Afghanistan, thereby eroding public confidence at home.

But a region director the Senlis Council, an international research and development group that maintains a presence in the war-ravaged nation, said it's overly simplistic and easy to blame the media.

Canadians have every reason to be asking questions because the Harper government failed at the outset to properly explain the dangerous mission and more importantly to set measurable objectives, said Edward McCormick.

"There are good moral and ethical reasons for the Canadian Armed Forces to be in Afghanistan," said the former Vancouver resident who now lives in Kandahar.

"There are good reasons for NATO to be there, but if they can't get that accountability and it isn't made plain and clear to all Canadians, then I think we're going to see in the near future more and more Canadians becoming very vocal about the unacceptable nature of this mission."

The telephone poll of just over 1,000 people was conducted between July 5 and July 9 - after the most recent Canadian deaths in Afghanistan. It has a margin of error of plus or minus 3.1 percentage points, 19 times out of 20.

Prior to the last Parliamentary debate in April 2006, the Taliban publicly outlined their straightforward strategy for fighting their guerrilla war against Canadians.

"We think that when we kill enough Canadians they will quit war and return home," said purported Taliban spokesman Qari Yuosaf Ahmed in an interview with The Canadian Press, conducted through a translator, over a satellite telephone.

Morton said the new poll is a reflection of the insurgent strategy, but doesn't mean they have won.

"They're very media savvy," he said. The Taliban believe "democracies are frail, feeble organizations that crumble at the first hard knock.

"That's what Hitler believed, that's what Stalin believed. They all had a similar judgment about democracy. They were wrong. It's not surprising the Taliban would take up that judgment. They really do think of us as contemptible."