MONTREAL - Encouraged by his upset performance in last month's Quebec election, Action democratique Leader Mario Dumont is now setting his sights on another elephant-sized task -- getting Quebec to approve of the Canadian Constitution.

Dumont has said the "1982 error" must be corrected and Quebec must be the "motor" of constitutional change.

If Prime Minister Stephen Harper's Conservative government is ready to open the debate on limiting federal spending powers, Quebec should take the initiative to get that into the Constitution, Dumont said on the weekend.

"It's regrettable that Quebec has been left outside the Canadian Constitution," the ADQ leader said Saturday.

The ADQ is the official Opposition with 41 seats and doesn't have any constitutional clout.

Yet, Dumont is already talking winning the next election, giving him a platform to push his agenda.

"We have to be clear-headed," Dumont said at a party meeting in Trois-Rivieres in central Quebec. "We can't let ourselves fall asleep after our real success on March 26. The next time, we'll be on the ground on Day 1 of the campaign with the best electoral machine in Quebec. That's the objective I am giving you."

Charest's Liberals were re-elected with a 48-seat minority government. Andre Boisclair's Parti Quebecois won 36 seats in last month's election.

Dumont has said he isn't a traditional federalist and wants more "autonomy" or powers for Quebec within Canada, but nevertheless rejects the idea of holding a third sovereignty referendum.

Though Quebec's new legislature won't meet until early May, relations between Dumont and Charest already appear tense.

Charest lashed into his ADQ counterpart over the weekend after Dumont suggested he wouldn't support the Liberal budget.

"It stunned me, it disappointed me and I think that many Quebecers have got to be disappointed to see that Mr. Dumont has taken such a hard-line attitude," Charest told a weekend rally in Quebec City.

But Dumont's constitutional gambit may simply be political posturing.

"This is all wishful thinking," constitutional expert Michael Biehels said. "This is Dumont trying to position himself in terms of his bargaining power with the Charest government."

"His true colours are coming out after the election, and it's obviously very clear that he's going to give Charest a rough time," said Biehels, who teaches at the University of Ottawa.

But even as Canada gets set to mark the 25th anniversary of the Charter of Rights and Freedoms this Tuesday, Dumont may quickly find there is little appetite to revisit the emotional debate.

"The federal government and the provincial government are in no position to go down this road," Biehels said.

"I don't think Dumont understands that the country has no stomach for any of this."