Economic turbulence rocked the prime minister Monday as he began the final week of the federal election campaign: stock markets plunged, European countries declared recessions, there was no sign of recovery in the United States, and polls suggested Harper's steady-as-she-goes message is falling flat with voters.

Some of the country's top economists predicted Canada is heading for a recession deeper and longer than anyone had anticipated. They suggested the economy could be hobbled until almost 2010.

Those dire warnings are in stark contrast to Harper's relentlessly optimistic forecasts throughout the campaign.

Three weeks ago, Harper declared the worst of the financial crisis to be over.

"My own belief is if we were going to have some kind of crash or recession, we probably would have had it by now," Harper, an economist, said in mid-September.

Ten days later, he pronounced that "the only way there is going to be a recession is if (Liberals are) elected."

Stock markets have plunged since Harper made that fearless prediction, including another triple-digit nose dive Monday.

Still, Harper maintained his stand-pat message.

"Let's be clear: the prime minister of Canada isn't going to go around the country predicting a recession when we're not in a recession now," he told a news conference in Ottawa on Monday.

"I remain fundamentally optimistic about the Canadian economy, but optimistic - as I've said from the beginning - within the framework that we're now living in, and that is a period of economic uncertainty.

"Look, we're not an island. We can't pretend, and we're not pretending, that we will escape effects of world developments."

Harper said the main problem is the tightening credit situation internationally.

"Our main advice is obviously to encourage co-ordinated action, to encourage actions that will stabilize the situation without creating a great deal of moral hazard for taxpayers."

Later, in an interview with Business News Network, Harper reiterated that he intends to keep the federal budget in surplus but he appeared to leave the door open a crack to running a deficit in future.

"There's nothing on the horizon - notwithstanding the storm clouds and they are significant - indicates to me that we should immediately go into deficit," he said.

He noted that some economists have argued that running a small deficit could help stimulate the economy in tough times but added that "once you cross that line," it's hard to prevent deficits from "spiralling out of control."

The prime minister has said the best way to deal with the current economic uncertainty is not to do anything sudden. He has accused Liberal Leader Stephane Dion of "panicking" for promising to convene a summit of political and economic leaders to deal with the economy within 30 days of taking office.

However, the no-change approach does not appear to be appealing to voters, according to the polls.

A new survey by The Canadian Press Harris-Decima suggests the Conservatives have dipped to 32 per cent support - a far cry from their campaign peak of 41 per cent and not enough to win a majority.

Dion's Liberals, at 25 per cent support, continued to lag behind the Conservatives but have been trending upward in recent days as they push a message critical of Harper's don't-panic response to the escalating economic turmoil.

Harris-Decima president Bruce Anderson said Harper needs to tweak his steady-as-she-goes message to show more empathy for Canadians anxious about the economy - and to show he has a plan to weather the economic storm.

But a senior Conservative spokesman indicated the prime minister won't spring any new, last-minute economic plan on Canadians when he unveils his party's platform on Tuesday.

That would be difficult anyway, given that Harper criticized Dion simply for proposing to discuss an action plan.

Dion and NDP Leader Jack Layton both bashed Harper's failure to respond to the economic crisis while painting themselves as the only alternative.

The Liberal leader said Harper is finally waking up and realizing Canada isn't immune to an economic crisis - but it's "too little, too late."

He simultaneously bashed NDP Leader Jack Layton for his vow to roll back $50 billion worth of corporate tax cuts - a proposal he labelled a "job killer."

In contrast to the ideological extremes of either the Tories or the NDP, Dion touted the Liberals as a centrist alternative with an impressive track record of managing the economy and balancing the books.

"We need real change, not false hope or misguided economic plans, especially in these times of financial uncertainty," Dion said during a campaign swing through Sidney, B.C.

Layton, with his New Democrats polling at 21 per cent support, began a shift in his campaign Monday with new television ads. One slams Harper's stand-pat economic message and another mocks Dion, declaring Layton as the only alternative to Harper.

Campaigning in Vancouver, Layton bashed Harper's "do-nothing attitude," while mocking the folksy, sweater-clad image the prime minister has been trying to project.

"I'll tell you what the problem with his do-nothing attitude is: pull one thread and the whole sweater unravels and it's the working people of Canada who get left out in the cold."

Layton characterized Harper as: "Scrooge to working families and their kids while being Santa Claus to the banks and oil companies."

The Greens were at 12 per cent in the latest poll, while the Bloc Quebecois had eight per cent nationally and was leading comfortably in Quebec.

The rolling sample represents 1,235 interviews conducted Thursday through Sunday. It is considered accurate to within plus or minus 2.8 percentage points, 19 times out of 20 - though the margin is much higher for regional samples.

More information on the survey is available at www.harrisdecima.ca.

Respondents were asked, "If a federal election were being held tomorrow, who do you think you would be voting for in your area?"