The PQ leader said she will still have the legitimacy to proceed even if Quebecers don't give her a majority in the 125-seat national assembly when they vote on Sept. 4.
The strategy of sovereigntist governance involves Quebec repatriating as many powers as possible from Ottawa as it moves toward full sovereignty.
Marois said a minority government must not prevent the PQ from moving ahead in various areas, including social policies and agriculture.
"At that point, we'd be renouncing governing," she said of doing otherwise.
Marois insisted she was answering a hypothetical question and that she's gunning for a majority.
Opinion polls have placed the PQ in first place in the polls, although it's still unclear whether it would have formed a majority had the election been held this week.
Money was doing a lot of talking among Marois' rivals on Friday as the leaders of the Liberal party and Coalition for Quebec's Future gave a glimpse of how they would handle the province's finances.
Premier Jean Charest said additional Liberal spending over five years would total $3.7 billion and respect the province's margin of manoeuvre.
"What we're proposing in this financial framework is in line with what we have done in recent years in controlling public spending," Charest said.
He said a re-elected Liberal government would stay on track to balance the budget and reduce the deficit to zero in 2013-2014. It would also impose cuts to provincial departments, agencies and Crown corporations.
It would also limit program spending to two per cent in 2014-2015.
Francois Legault, head of the Coalition for Quebec's Future, said he would aim for a zero deficit in his first year in power.
He outlined that his electoral promises would cost $1.8 billion and that he would also cut income taxes by $1.8 billion — measures that would be paid for by eliminating billions in government "waste."
The cuts would take place over five years and include a reduction of $600 million in expenses at Hydro-Quebec. Legault also wants to abolish health agencies, reduce purchases in health and education and lower dispensing fees for the province's pharmacists.
"I'm not looking to be friends with Jean Coutu," he said, referring to one of the province's largest drugstore chains.
The savings would go toward providing every Quebecer with a family doctor. Education would receive the lion's share — $1 billion over five years. There would also be assistance for Quebec families, including tax credits for day care and those buying their first home.
"We will deliver the goods," Legault said.
Marois, who has said she will not say how much her promises will cost until after the leaders' debates this coming week, ridiculed Legault's proposals, in particular the one promising each Quebecer with a family doctor.
Marois got a boost Friday from a former Liberal cabinet minister who had threatened to run as an Independent against Charest in his home riding.
Marc Bellemare announced he is throwing his support behind PQ candidate Serge Cardin, who represented Sherbrooke for the Bloc Quebecois between 1998 and 2011.
"Years of favouritism and cronyism have made the Charest government the most corrupt government in the recent history of Quebec," Bellemare said.
Bellemare is a former Charest cabinet minister who alleged a few years ago that Liberal party fundraisers influenced the selection of judges.
Charest and Bellemare then sued each other over the issue before eventually agreeing to drop legal proceedings.
Cardin says he is happy Bellemare is not running because of possible vote-splitting.
"We are pleased to learn that Marc Bellemare is supporting us," a spokesman for Cardin said in an email. "Mr. Bellemare understood he would have split the vote....
"Like a majority of Quebecers, Mr. Bellemare considers that Quebec deserves more than a corrupted and washed-up government.
One recent poll suggested Cardin was leading Charest by 15 percentage points. The Liberal leader has represented Sherbrooke since 1998.
Bellemare left the Liberals in 2004 after they failed to fulfil an election promise to kill the province's no-fault insurance law — legislation he has staunchly opposed for years.
(By Nelson Wyatt in Montreal with files from Martin Ouellet, Alexandre Robillard and Stephanie Marin)
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