Monique Gagnon-Tremblay said Charest is scheduled to meet his outgoing cabinet Wednesday and then his caucus later in the week, possibly Thursday.
Gagnon-Tremblay expects Charest to talk with his colleagues at those gatherings about whether he should stay on as Liberal leader.
"Yes, probably, because he's always consulting his caucus," she said at the Liberal rally in Charest's home riding of Sherbrooke, minutes after he gave his post-election speech without offering a hint about his future.
"He will do it, I'm sure, as he's used to doing it."
Charest suffered two major defeats Tuesday. His Liberal government was relegated to the official Opposition after nine years in power and he lost his hometown seat of Sherbrooke for the first time in nearly three decades of federal and provincial elections.
His first-ever win came on Sept. 4, 1984 — 28 years to the day before Tuesday's loss.
The Liberal defeat also brings Charest's run as Quebec's leader to an end — leaving Ontario's Dalton McGuinty with the longest active streak by a Canadian premier.
More than 100 Liberal supporters, who had been watching voting results roll in on a giant TV screen, sat in stunned silence as their local political hero lost his government, and then his seat.
Except for a couple of gasps and some red, watery eyes, the disappointed rally participants barely made a peep when they learned that Charest's Liberals had lost the election.
Most inside the Sherbrooke hotel also remained quiet when reports later indicated Charest had lost his riding to Parti Quebecois candidate Serge Cardin — but a handful of them booed.
Charest was quick to take responsibility for the losses.
In a passionate concession speech, Charest said the Liberals once again proved the polls wrong by coming just one percentage point shy of the PQ for the overall popular vote. Surveys had suggested a much-larger gap between the parties.
Charest was also pleased that the sovereigntist PQ was only handed a minority mandate, likely enough, he said, to keep its independence aspirations in check.
"I want to say to all of you tonight, and to all of you interested in the future of Quebec, that the result of this election campaign speaks to the fact that the future of Quebec lies within Canada," Charest said, drawing a big applause from the crowd.
Charest said that much work is left to be done and the Liberals will have opportunities to contribute to Quebec's future under the minority government.
He did not, however, offer any indication during the 13-minute address whether he would be part of the next phase.
Gagnon-Tremblay, a longtime friend of Charest's, said she didn't know what he will decide to do next.
"He will have to choose, he will have to decide — there's always a life after politics," said Gagnon-Tremblay, who did not seek re-election.
"He will take some time before deciding something. He's not in a hurry."
One supporter at the rally didn't know what will happen with the party or Charest.
"A lot of people are disappointed, let's put it that way," Jimmy Sawchuk said.
"It will be hard for him to leave politics. Is the party going to hold (together) if he leaves politics? We don't know."
It was the first time Charest, 54, lost his own seat in his political career — a stretch that took place entirely in this city.
Charest, who won eight consecutive votes at the federal and provincial levels, had clung to his riding despite several close calls over the years.
He won the seat in 2008 by 2,314 ballots. A year earlier, he squeaked out a win by 1,332 votes. On election night in 2007, one TV news outlet had even erroneously declared Charest had lost his seat.
Charest also endured the devastating 1993 Progressive Conservative defeat that left the party with just two seats across the country.
But this time around, despite uncharacteristically making several campaign stops in Sherbrooke, it just didn't come together.
Earlier in the campaign, Cardin, a former Bloc Quebecois MP from the area, said locals had been telling him they were fed up with the premier and the "odour of corruption" around his Liberal party.
This is the second time Cardin will succeed Charest in a political office. Cardin won Charest's vacant seat after he left federal politics in 1998.
With Tuesday's results, the province has turned the page on a premier who led Quebec during an era that saw the province's appetite for independence decline.
One political scientist believes Charest deserves credit for subtly helping reduce support for sovereignty, which the latest survey indicated was at 28 per cent.
Bruce Hicks, of Concordia University, said Quebecers stopped focusing on what was wrong with the federation because the Liberal leader was only occasionally confrontational in dealing with Ottawa. Charest also stopped pressing for constitutional change and instead promoted bread-and-butter issues.
"I do actually think that his approach to politics, his approach to Ottawa and the other provinces, was a game-changer," he said.
But Hicks doesn't think historians will give Charest the recognition he deserves for his contribution because his approach was much quieter than larger-than-life opponents to Quebec sovereignty, like Pierre Elliott Trudeau.
Instead, Hicks predicts people to link the drop in support for sovereignty to the uncertain economic situation.
He said another aspect of Charest's legacy comes from his attempts to reduce state intervention and retool the provincial pension-fund manager — the Caisse de depot et placement du Quebec — to make investments that reap returns, rather than use it to protect Quebec companies.
The world financial crisis helped sideline Charest's plans, he said.
"He put this discourse into the public arena," Hicks said.
"It would have been heresy a decade ago for anyone to suggest that the Caisse de depot should simply make investments because they have a good return."
The province's unemployment rate is far closer to the national average than it was when Charest took office. He made good on his 2003 promise to reduce income taxes, but his pledge to "re-engineer" Quebec's state, to make it smaller, was derailed.
The provincial debt has ballooned, especially after the financial crisis. The Charest government responded to the budget crunch with user-fee hikes in several areas, including university tuition.
The tuition gambit triggered massive student demonstrations in the streets this spring, sometimes-violent events that made international news. Many of the protesters also railed about the multiple ethics and corruption scandals that forced Charest to call a public inquiry.
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