Conservative Leader Stephen Harper found himself on the defensive in the final televised debate, with the other party leaders combining forces to attack his record on the economy and environment.

Harper attempted to distance the country's economy from the financial troubles in the United States, saying Canada's banks remain strong.

"We have not been following the same economic policies as in the United States that have led to that mess. We have not made those choices, which have been disastrous," he said. "We've made very different choices in Canada and we have a surplus."

NDP Jack Layton fired back: "The economy is not fine. Any Canadian will tell you that. Either you don't care or you're incompetent. Which is it?"

Bloc Quebecois Leader Gilles Duceppe attacked Harper on failing to help Canada's struggling manufacturing sector -- a major issue in Quebec and Ontario.

"I don't see how you can say you're helping the manufacturing sector when you say you're giving them tax breaks," he said. "They're not making any profits, so they're not paying any taxes."

Despite the frequent attacks, Harper appeared largely relaxed for the first hour, but occasionally showed the tight smile he displayed in Wednesday's debate.

Many of the most biting remarks came from Layton, although his one- or two-line jabs sometimes appeared to fall flat.

"Where is your platform? Under your sweater?" he asked Harper at one point, referring to recent campaign ads meant to portray the leader's softer side.

Layton also accused Harper of not caring about the workers who had lost their jobs in the manufacturing sector.

"I've been between jobs, I understand that," Harper responded. "But what we have to do as leaders is make sure we have a plan to create jobs."

On the economy issue, it was rare for Harper's opponents to target one another. But at one point, Dion told Layton that the NDP pledge to raise corporate taxes was not the correct way to help Canada's economic growth, and that the government should also shift taxes to pollution.

"To cut the corporate tax is something the Liberal government did well before Mr. Harper. It's not a right-wing policy, it's not a left-wing policy, it's a sound policy," he said.

Originally, the economy was only allotted 12 minutes of the debate but was given 30 minutes because of the U.S. financial crisis and Canadian's own economic woes. Wednesday's French debate followed the same format.

On Thursday, Toronto's S&P/TSX composite index plummeted 813.97 points to close at 10,900.54 -- its lowest level in about two years.

South of the border, the Dow Jones industrial average also lost 348.22 points, despite the U.S. Senate approving a revised bailout plan that's now headed to the House of Representatives.

Environment

On the topic of the environment, Green Party Leader Elizabeth May said Canada must go back to its Kyoto obligations and cut greenhouse-gas emissions by 1990 levels. Under the Conservative plan, reductions would be measured by 2006 levels.

She accused Harper of helping to derail Kyoto at various international climate-change conferences.

"It's a shameful situation for Canadians to know that our government sent our negotiators to international conferences such as Bali, and obstructed progress even more than the Bush administration," she said.

Dion said Harper's environmental plan had been rejected by most economists, and promoted his own Green Shift plan.

"We'll cut taxes on economic activities that are creating wealth, like investments and profits, and we'll put the price on pollution," he said.

Harper responded that he would introduce tough targets for greenhouse-gas emissions for companies operating in the Alberta tar sands, and noted that he had worked hard to protect Canada's conservation areas.

"We've signed an important agreement with the Nature Conservancy of Canada to preserve hundreds of thousands of hectares of environmentally-sensitive land, mainly near cities," he said.

Harper also noted the Conservative government had expanded Canada's parks system, created the largest marine park in the world -- located in Lake Superior -- and a whale sanctuary in Baffin Island.

Afghanistan

All of the party leaders were asked whether they stood behind a firm 2011 deadline to remove Canada's troops from Afghanistan.

Harper said he fully supported the deadline, disagreeing with other Western leaders who suggested they would maintain their military commitments indefinitely.

"If we are to truly pacify that country and see its evolution, we have to train the Afghan army and police so they are credibly able top take greater responsibility for their security," said Harper.

"We won't achieve such a target unless we actually set a deadline and work to meet it."

Dion praised Canada's soldiers for working to better the lives of Afghans, and said Canada had good reason to be involved in the war-torn country.

"If I thought for a minute that we were there as invaders, I would ask that we pull out our troops immediately. We as Canadians always put our troops abroad to help in the cause of peace, security and democracy," he said.

But he suggested he would follow the 2011 deadline.

"In 2011, we will have other responsibilities in Darfur and other countries. It's what we would do as a Liberal government," he said.

Health care and the arts

Layton accused Harper of trying to privatize Canada's health care system, an attack he has frequently levelled against the Conservatives in the past.

He said Harper once led the National Citizens Coalition, which has as "one of its main objectives" the push for private health care.

"And now you want a majority government?" Layton asked.

Harper fired back that Layton once visited a private clinic in Ontario called the Shouldice Clinic, which accepts the provincial health card.

The arts was another major issue during the debates, with Harper's rivals once again ganging up on the Conservative leader and taking him to task for past comments.

May suggested the Conservatives had cut arts funding for purely political reasons.

"Your tacticians and strategists have decided that these mean-spirited cuts against artists will win you votes, and that's the whole reason for these stupid cuts," she said.

All five party leaders were seated around a table, rather than standing behind podiums, and the debate was moderated by journalist Steve Paikin.

Wednesday night's televised French-language event also saw Harper targeted by his four opponents early on, mainly over his policies on the economy and the environment.

A La Presse poll in Quebec found most people who watched Wednesday's French-language debate felt Bloc leader Gilles Duceppe and Liberal leader Stephane Dion came out as the winners.