Liberal Leader Philippe Couillard said if he becomes premier on April 7, he'll push federal, provincial and territorial officials to take Quebec's unique status into account in any constitutional talks.
"I was absolutely flabbergasted to see Mr. Couillard wants to do this," Marois said.
She wanted to know whether Couillard will consult Quebecers on their demands and whether he even knows if Prime Minister Stephen Harper is interested in reopening constitutional talks.
The status of distinct society for Quebec has been a minefield for Canada's political leaders in the past.
Pro-independence forces have repeatedly cited the absence of Quebec's signature on the 1982 Constitution as an example that federalism is a failure.
Efforts to get Quebec included in the Constitution in then-prime minster Brian Mulroney's Meech Lake accord of the late 1980s failed.
Mulroney also struck out with 1992's Charlottetown Accord, which sought to recognize Quebec in the Constitution's preamble as part of a so-called Canada Clause.
Both failures helped to energize sovereigntists in Quebec.
The most recent attempt at recognition has been Prime Minister Stephen Harper's successful 2006 motion in Parliament to have the Quebecois acknowledged as a nation within a united Canada.
Couillard plans to go across the country to press his case to federal, provincial and territorial officials.
"My first message will be about the economy and jobs," he said during a campaign stop in Val-d'Or. "I will always mention the need that some day the specific character of Quebec will be recognized formally in our Constitution."
The focus on Quebec's constitutional status came as Marois tried once again to shift the focus of the election away from sovereignty-related issues.
Barely two minutes into the question period of a news conference to discuss the PQ's social economy platform, Marois was again peppered with questions about whether she is ready to lead sovereigntist forces in a referendum or what the transition period would be after a Yes win.
She said any talk about a post-referendum transition period was hypothetical and that she wouldn't address it further.
The PQ leader chuckled when she responded about her readiness to lead the Yes side, saying the current election is about choosing a government.
"We're sovereigntists and we will never refuse to speak about sovereignty," she said.
"On the contrary. We will continue to do so but we are also able to speak about the economy, culture, the social economy, regional development, and that is what we'll do as we go toward the April 7 election."
The PQ usually treads carefully around sovereignty in election campaigns because threats of another referendum have often alienated soft nationalists who remember the divisive sovereignty votes in 1980 and 1995.
Where Marois had recently been speaking freely about a lack of borders and the sharing of a common currency with Canada in a sovereign Quebec, her tone has changed in recent days to little more than promising to draft a paper on Quebec's status in the federation if she forms the next government.
On Friday, Marois said that regardless of the outcome of the consultations on the paper, the government will have the final word. She also said there has been no decision on how the consultations will be conducted but all opinions will be welcome.
The sovereigntist leader also attempted to reassure Canadians on Friday that they shouldn't fear the outcome of next month's election.
Marois said relations between Quebec and the rest of Canada have been good for the past 40 years, regardless of whether her pro-independence party or the federalist Liberals have been in power.
"We will continue to have very good relations with the rest of Canada even if we are sovereigntist," she told a news conference.
Marois's relations with star PQ candidate Pierre Karl Peladeau figured as prominently in her day as relations with Canada.
She was asked about a comment she made in a morning radio interview that Peladeau is not her heir apparent as PQ leader.
"I'm not ready to leave my function," Marois said. "I am at the head of the Parti Quebecois. I'm very proud to be here and I want to be premier of Quebec for the next mandate, so there is no place for another person."
Marois also took a dig at Bob Rae, telling him to "mind his own business" after she was informed the former federal Liberal leader said a Quebec civil servant or trade unionist voting for the media magnate is "like a chicken voting for Colonel Sanders."
Marois tried to placate Quebec's union movement, elements of which have criticized the PQ for enlisting Peladeau's services because of his stormy relations with the labour movement over the years.
"When Mr. Peladeau decided to join my party, he accepted the program of my party," she said. "My party is respectful of unions. There is no problem with the presence of Mr. Peladeau in my party about this issue."
In other campaign news, the PQ announced it won't field a candidate against Fatima Houda-Pepin, a former member of the Liberal caucus now running as an Independent.
The PQ is urging its members to back Houda-Pepin in La Piniere on Montreal's south shore.
Houda-Pepin, the only Muslim female member of the legislature, was expelled from the Liberal caucus in January over her pro-secularism stance.
A staunchly federalist member of the national assembly since 1994, she is running against Liberal star Gaetan Barrette.
Coalition party Leader Francois Legault also announced he would hire 500 new specialists, such as psychologists, for Quebec schools if he becomes premier.
— With files from Martin Ouellet, Peter Rakobowchuk and Etienne Fortin-Gauthier in Montreal and Julien Arsenault in Val-d'Or
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