On the eve of an election call, Prime Minister Stephen Harper says he's anticipating a "very nasty" campaign from the opposition parties, in an exclusive interview with CTV News.

Harper is expected to call an election Sunday morning, with Canadians going to the polls on Oct. 14 -- despite his party's own legislation that set a fixed election date for October 2009.

In an exclusive interview with Harper to be broadcast Sunday on CTV's Question Period, he said he expects the opposition parties to try to demonize him.

"To be really honest, I anticipate a very nasty, kind of personal-attack campaign," he told Lloyd Robertson, CTV's chief news anchor and senior news editor, at Harrington Lake.

"That's just what I'm anticipating; that's what the opposition's done in the past. I think that whether Canadians agree with what we're doing or not, I don't think they're going to believe the kind of personal attacks and scare tactics that we've seen in the past."

Harper also defended his choice to ask the Governor General for an election. In the past, he has called Parliament too "dysfunctional" to continue.

"The Opposition doesn't want to support the government any longer for anything," he said. "The government doesn't want to change direction ... You know, everybody around Ottawa knows this Parliament has reached its useful end."

All of the parties are ready to launch their campaigns on Sunday, although it appears the Liberal have had problems getting their plane ready.

The New Democrats have taken their campaign bus for a test spin and the Conservatives are running election ads, but the Liberals are scrambling to fix up a Boeing 737 made in 1979.

The Air Inuit plane is not expected to be ready until near the end of the week. Conservatives say it's a blunder on the part of Liberal Leader Stephane Dion.

"I think this underscores his weak leadership and what a risk he would be as prime minister. He can't even lead his own party," said Conservative MP Jason Kenney.

Liberal MP Bob Rae, speaking in his Toronto riding on Saturday, said his party is well prepared for the election -- despite the delay in getting a plane.

"We're ready to go," he said. "The only transportation I need in Toronto Centre are my feet, and they are in good shape."

A recent Strategic Counsel poll suggested the Conservatives have an eight-point lead over the Liberals, but Rae said his party has a "great chance of being successful" in the looming election.

Rae also said he will do whatever he can to help Dion, who he said is a "very tough cookie," to become prime minister.

The Strategic Counsel poll for CTV and the Globe and Mail gave top leadership marks to Harper, followed by NDP Leader Jack Layton. Dion came in third. But Rae said Dion didn't have any weaknesses as a leader.

Meanwhile, in a new NDP ad released Saturday, the left-leaning party took aim at Harper's leadership.

The ad claimed that Harper cut corporate taxes by $50 billion even though one in eight Canadian children lives in poverty.

Harper is "strong enough to ignore nearly five million Canadians who can't find a family doctor," a female announcer intones before linking oilsands development in Harper's home province of Alberta to environmental devastation.

"We need a new kind of strong," she says.

Layton then tells the viewer: "The 'new strong' is about fighting for what's right for you."

While the NDP spent as much time attacking the Liberals in the last two years as the Tory government, neither Dion nor the Liberals are mentioned in the ad.

"I think the ad really speaks to our central message, which is that we have a leader who is prepared to replace the prime minister," NDP president Ann McGrath told CTV Newsnet on Saturday.

On the Conservative party's website, virtually all of the attacks are aimed at Dion, not Layton.

Meanwhile, the Conservatives released new television ads this week showing Harper's softer side, where he talked about playing cards with his children.

Conservative strategist Goldy Hyder told Newsnet that a key question in the looming campaign will be who is best qualified to manage both the federal government and the overall economy.

Geoff Norquay, another Conservative strategist, told Newsnet that Harper was the safe, steady choice and that picking Dion would be risky.

With a report by CTV's Rosemary Thompson in Ottawa and files from The Canadian Press