OTTAWA — The biggest handicap facing the Liberals is not the sponsorship scandal, but a deep-rooted desire for change, a new poll suggests.

The Decima survey turns conventional wisdom on its head by suggesting voters' inclination for a change in government dwarfs their anger over sponsorship.

Only 35 per cent of respondents who said they wanted to replace the government cited the scandal as their prime motivation.

A far greater number - 57 per cent - said it was because the Liberals have been in power too long and they wanted a turnover after 12 years.

The poll surveyed 1,040 respondents between Nov. 17 and 20, and its findings are said to be accurate to within 3.1 percentage points, 19 times out of 20.

With an election campaign set to begin next week, the poll offers guidance to all parties, especially the Conservatives.

"The Conservatives have a choice in front of them," said Decima chief executive Bruce Anderson.

"There's a question of whether or not voters will want to spend the bulk of the election campaign talking about the future or talking about the past."

The Liberals are already making extensive use of another survey conclusion: that voters are extremely skittish about Conservative Leader Stephen Harper.

The poll suggests Harper's personal unpopularity helps sustain the Liberal party; almost 40 per cent of people who said they would vote Liberal cited Harper as their main motivation.

Another 52 per cent said they favoured the Liberals because they disagreed generally with Conservative policies.

The Liberals spent a large part of the last campaign demonizing Harper as a threat to Canada's established values, and they plan to paint a similarly scary portrait this time.

Harper could fight back by fanning outrage over a 1990s scandal, but he'd be much better off if he also excited moderate voters with his own policies, Anderson said.

"There's no guarantee the Conservatives would lose an election if they ran just on sponsorship. But there's less evidence to believe they'd win it if they ran only on sponsorship."

Recent polls have placed the Liberals between four and eight percentage points ahead of the Tories, with the NDP running stronger than usual in the 20-per-cent range.

But incumbent governments tend to dip in support during election campaigns and Anderson warns this one will be anybody's game.

The campaign could be unusually long -- up to seven or eight weeks, with a break for Christmas.

The Tories can't expect to surf on scandal that long; they must appeal to voters who could swing either way, Anderson said.

"The larger challenge for Conservatives is about convincing voters that they would be more mainstream or centrist," he said.

"This is likely a bigger challenge than it would be because of the fact that Harper's political biography is more often associated with right of centre policy, the Reform party, and western alienation."

The campaign hasn't even begun and the Liberals have already suggested Harper is a lackey to U.S. President George W. Bush, is in bed with the separatist Bloc Quebecois,, lacks an environmental policy, would institute draconian tax cuts, gut social programs, cut cultural subsidies and has thwarted increased funding for the Immigration Department.

The Tories insist they will deliver an intricate policy platform aimed at exciting voters.

They also have counter-arguments planned for the bogeyman theme: that Liberal scandal helped revive the Bloc, that the prime minister's relationship with Bush is so poor it took weeks last summer to organize a telephone call on softwood lumber, that Liberals don't even have a plan to meet pollution control targets and have turned the immigration system into a bungled, bureaucratic mess.