Generally, Harper is expected to hammer home his key campaign messages of strong economic stewardship, low taxes and job creation, but he will specifically be trying to shore up existing Conservative support in the five ridings the party was left holding after the 2011 vote.
"I think it's reasonably well understood and assumed that all of Quebec is not in play for the Conservative party," said Tim Powers, a Conservative strategist who is not advising this campaign.
"I suspect (Harper will make) a very direct pitch to the pockets of Conservative voters in Quebec who are going to be crucial," particularly in the Quebec City region, where most of the party's seats remain, he said.
One issue that has been controversial in many parts of the country but will appeal to the Conservatives' base in Quebec is that of niqabs at citizenship ceremonies.
The federal government is fighting a court ruling that threw out the requirement for uncovered faces at the ceremonies.
The Conservatives are banking on the issue being a winner for them in Quebec, releasing a French ad this week with Harper sitting around a table, telling a few assembled people that Quebec values are Conservative priorities: reducing taxes, good jobs, a good future for their kids, a comfortable retirement — and new citizens who take the oath with an uncovered face.
The niqab debate in Quebec is different than in much of the rest of Canada, said McGill political science professor Antonia Maioni.
"Mr. Harper's position was yes to diversity but there are certain limits," she said. "I think it's that image of a boundary that may appeal to voters in Quebec."
Since this will be the first national leaders' debate involving Bloc Quebecois Leader Gilles Duceppe — all five party leaders, including Green Leader Elizabeth May, are participating — sovereignty will certainly be much discussed.
The issue briefly appeared during the Maclean's debate in August, when Harper and Liberal Leader Justin Trudeau hammered NDP Leader Tom Mulcair for his support of the so-called Sherbrooke Declaration of 2005. It endorses the principle of recognizing a referendum victory by the sovereigntist Yes side even by a majority of just 50 per cent plus one.
Harper is in a relatively comfortable position on sovereignty, Powers said, as he has been through several French-language election debates before in which he has addressed the issue. He can also remind Quebec voters that he was responsible for a motion that recognized Quebecers as a nation within Canada.
"(That), I think, gives him insurance to deal with any trickier circumstances" on sovereignty, Powers said.
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