The Parti Quebecois leader's tempered approach came after poll results suggested the pro-Canada Liberals had gained ground in the Quebec City area at the expense of the third-place Coalition party.
The survey, taken after Peladeau was named a PQ candidate, appeared to show that federalists in the region had begun to rally under the Liberal banner with hope of avoiding a referendum.
The PQ's tactical change was apparent Thursday when Peladeau, one of Canada's most-powerful media moguls, suddenly refused to answer questions about Quebec sovereignty or any future vote on independence.
Marois told reporters at their joint news conference she was running an election campaign, not a campaign on the future of Quebec.
"When Quebecers go to the polls on April 7, they will be voting for a government," Marois said at the event outside Quebec City, with Peladeau standing nearby.
The PQ's abrupt reluctance to promote sovereignty came after Marois spent a couple of days describing what life would be like in an independent Quebec, where she said citizens would maintain a customs-less border, keep using the Canadian dollar and request a seat at the Bank of Canada.
The change also came just a few days after Peladeau's splashy entrance Sunday into politics, where the celebrity owner of Quebecor Media Inc. (TSX:QBR.B) pumped his fist into the air, proclaimed his lifelong passion for Quebec sovereignty and answered numerous questions on the topic.
Peladeau, however, had a much different approach at Thursday's event.
He refused to give direct answers to independence questions — in other cases, he just didn't say anything at all.
"Today, we're talking about the economy, we're talking about entrepreneurship," Peladeau said in one response, as he stuck to a script related to the theme of the announcement.
By the end of the 35-minute news conference, the rookie politician appeared to have grown tired of the queries.
That's when a reporter asked Peladeau whether he was the man who would break up Canada, making reference to a front-page headline in Macleans magazine.
"We're here to talk about economy," he repeated in a raised voice, before ending the sentence with an awkward laugh.
"I just mentioned to your colleague earlier that this is the purpose of my presence here. And this is the purpose of also what I consider my engagement in politics."
Marois, meanwhile, tried to play down the sovereignty angle by repeating her promise that a majority PQ government would consult Quebecers before holding another referendum.
In raw numbers, Thursday's Leger Marketing poll for Quebec City's FM 93.3 radio station found that the Liberals led the PQ by seven percentage points.
With the margin of error of 3.86 percentage points factored in, however, the parties could be in a statistical tie.
The poll's 643 respondents were surveyed this Tuesday and Wednesday.
The impact of Peladeau's arrival with the PQ remains unclear.
Peladeau, also known as PKP, has been both a popular and polarizing figure in Quebec.
His emergence as a candidate for the PQ was a surprise since the businessman has gone to war against unions, traditional supporters of the party.
Many also believe a man of his stature would not enter politics if he didn't have his eye on Marois's leadership job.
Quebec has been fascinated by the dynamic between the multimillionaire magnate and the PQ leader, likely one of the few people he's had to answer to in recent years.
Even though most of the questions Thursday were directed at Peladeau, Marois jumped in a few times and answered for him.
At one point, she gently pushed him away as he tried to approach the microphone.
Marois, who has been overshadowed by Peladeau on the campaign trail, decided she wanted to field a question for him about how his political aspirations could create a potential conflict of interest related to one of his businesses.
"I'll answer this," Marois could be heard telling Peladeau through the podium mic, as she put her hand on his shoulder and moved him aside. He nodded and stepped back without saying a word.
She was later asked whether Peladeau had become a liability for her campaign.
"I am very proud to have the presence of Pierre Karl Peladeau in my party," Marois said of her candidate in the Saint-Jerome riding, a critical swing seat north of Montreal.
"He's a man who built a great business and he's an example of success in Quebec and I hope that (he) will be a model for the young Quebecers who want to do business in Quebec."
Peladeau's proclamation in support of sovereignty at his coming-out event made the issue an unexpected focal point of the campaign, particularly since recent polls have suggested only about 40 per cent of Quebecers support independence.
Liberal Leader Philippe Couillard has given repeated warnings the PQ would lead the province to a third referendum on independence if it wins a majority mandate.
On Thursday, Couillard attacked Marois's earlier remarks that citizens of a sovereign Quebec would continue to enjoy many of the benefits of Canada. He called those assertions an "unprecedented festival of confusion."
"An imaginary world, confusion, are trademarks of this movement, which knows that without confusion and without an imaginary world, it is unable to convince a majority of Quebecers about the validity of its direction," Couillard told a news conference before the Marois-Peladeau event.
"I'm not even sure if her own intentions are defined."
Later Thursday, Justin Trudeau offered his support to Couillard, making him the first federal political leader to publicly back a Quebec candidate. Members of Trudeau's Liberals offered support for the Quebec Liberals last week.
"My Quebec colleagues and I support federalism, @phcouillard and the #QLP," read a tweet on Trudeau's Twitter feed.
A subsequent tweet read: "Quebecers want a better economy, not a third referendum."
Coalition party leader Francois Legault said Thursday that when political leaders start talking about referendums, Quebecers return to their old habits of voting for either the pro-independence PQ or the federalist Liberals.
"With the Coalition, there will be no referendum," Legault said of his right-of-centre party.
"They're used to seeing the Liberals give answers like that, but on top of this, we'll cut taxes."
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