Identity politics gave the PQ an edge in the 2012 campaign and language was to be one of its priorities in the campaign for the April 7 election, right behind the party's proposed secularism charter.
Both issues had to take a back seat to sovereignty only a few days after the election was called because of remarks by star candidate Pierre Karl Peladeau and Marois herself in favour of an independent Quebec.
The talk of another referendum — which is generally disliked by most Quebecers — derailed the PQ campaign and Marois has since been trying to get back on message.
The PQ got new wind in its sails Friday after Liberal Leader Philippe Couillard was pummelled during Thursday's televised debate and was accused of being soft on the protection of French.
Marois took full advantage during a news conference where she had already planned to discuss the PQ's plans on the matter.
"We think it's important to adopt a new French Language Charter because I think in Montreal we have real problems on this issue," Marois said, adding the Liberals are to blame for that.
"We want to live in French, to work in French. That is very important."
The new measures would include making it obligatory for students in English-language junior colleges to prove their competency in French before being allowed to get their diploma.
Francophone students would still have access to higher education in English.
The PQ would also look at bilingualism requirements in hiring and ensure they are really necessary.
Marois, who has polished her English in recent years but refused to participate in an English debate, insisted she has nothing against individual bilingualism.
"If you want to be bilingual, I agree with you as a person. But as an institution and as government, I think the official language of Quebec is French and we don't have to be bilingual in our institutions."
Language has always been a hot-button issue in Quebec politics and a potent wedge for the PQ amid fears in certain quarters that French is under constant threat, particularly in Montreal.
The Liberals are often accused of catering to the anglophone community because they draw a significant amount of their support there.
The fluently bilingual Couillard moved to reassure voters on Friday that protecting the French language is crucial.
The Liberals need to prevent any further bleeding of the key francophone support, which determines the winner in most of the province's 125 ridings and is traditionally stronger for the PQ.
Couillard maintained that the French Language Charter — better known as Bill 101 — is sufficient in its current form but needs to be applied rigorously.
"Always in North America, French will need special attention," he said. "And I think all Quebecers, including English-speaking Quebecers, recognize that.
"We must respect and apply Bill 101 as it stands today. As for going forward and protecting and promoting French, for us the solution goes better with teaching it better, writing it better, speaking it better, teaching it faster for newcomers to Quebec."
Still, he touted the benefits of speaking both French and English.
"It's always a great advantage for anyone to be bilingual. I know. And this is something the Pequistes don't want me to say but I'll say it again — there's not a single parent in Quebec who doesn't hope for their kids to be bilingual. It's such a fantastic asset in life."
Marois wasn't the only one to knock Couillard's stand on defending French. Legault appeared disgusted about it.
"It was pathetic to hear Philippe Couillard last (Thursday) night on French," Legault said. "I have never seen a leader of the Liberal party hesitate to defend French . . . . It was pathetic to see Mr. Couillard not defend the Quebec identity last night."
Late Friday evening, Quebec's two largest unions also weighed in, sending out statements blasting Couillard.
The Confederation of National Trade Unions and the Quebec Federation of Labour accused Couillard in separate news releases of downplaying the importance of French in the workplace and said it would be unacceptable to let it suffer in any way.
Unions have been traditional supporters of the PQ but even that party incurred their wrath with the candidacy of Peladeau, who is known for his frequent use of lockouts in labour negotiations.
Language wasn't the only area where Couillard faced questions. He also had explain again his decision to place money in an offshore tax haven while practising as a neurosurgeon in Saudi Arabia well before beginning his political career.
Couillard said there was nothing illegal about the account and that he paid taxes on the money in it upon his return to Canada.
Although the focus of the campaign moved to language and ethics on Friday, sovereignty wasn't completely absent.
Quebec's chief electoral officer apologized after a spokesman said the referendum process would be triggered immediately if the PQ formed a majority government.
Jacques Drouin said in a statement such a scenario is not being considered.
Drouin said the Quebec law dealing with plebiscites needs to be updated before any referendum process is started.
He was responding to comments that spokesman Denis Dion made in an interview with Quebec Le Soleil.
Dion told the newspaper it was obvious that a PQ majority victory would kickstart the referendum machine.
Marois has repeatedly stated there will be no referendum until Quebecers are ready for one and did so again on Friday.
That reluctance was also echoed by star PQ candidate Jean-Francois Lisee, who softpedalled the appetite for a possible referendum if sovereigntists form a government.
He observed that Quebecers have a "big fear" of a third referendum and aren't ready to vote on the issue again. Previous referendums were held in 1980 and 1995.
"I'm always optimistic about sovereignty, you know," he said. "I've rarely been as pessimistic as I am now.
"I was really struck by the message Quebecers sent at the start of this campaign. Very struck. I am pessimistic at the possibility of having a referendum in a first mandate."
Marois said she had gotten the message too.
"If they don't want it, I am capable of hearing them," she said.
— With files from Canadian Press reporters Melanie Marquis, Pierre St-Arnaud and Etienne Fortin-Gauthier in Montreal, Julien Arsenault in Blainville andin
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