NDP Leader Tom Mulcair is seeking provincial allies as he's "turning on the light to Senate abolition" just as the premier of this home province of Quebec spoke out against the plan.

Quebec Premier Philippe Couillard said Wednesday abolition is against the political interest of his province.

"Clearly, because the percentage of the population of Quebec is diminishing over the years, we need a place where we can find a balance in terms of regional interest — and it's in that spirit that the Senate was created," Couillard said.

Last year, the Supreme Court shot down the federal government's plan for Senate reform, ruling that changes would require approval of at least seven provinces that represent at least half the population. The top court also ruled that abolishing the Senate would require consent of all the provinces.

Prime Minister Stephen Harper called the ruling a "decision for the status quo" that left the federal government stuck on plans to reform the Senate.

But with the federal election approaching, Mulcair vowed Wednesday to keep his eye on the scandal-ridden Senate, the subject of a scathing auditor general report this week that detailed nearly $1 million in questionable expenses claimed by current and former senators.

"I'm going to be turning on the light to Senate abolition," he said. "I'm going to work non-stop. I'm not going to be like Stephen Harper, who threw in the towel on Senate abolition."

Trudeau calls for 'real' Senate change

Liberal Leader Justin Trudeau said Wednesday that abolition would require "a huge amount of negotiations with the provinces" at a time when the federal government should be focusing on "jobs, climate change and the path forward."

liberal leader justin trudeau

Liberal Leader Justin Trudeau said he wants to see 'real change' in the Senate, rather than abolition. (CBC)

He argued that Canadians want "real change in the Senate," such as his move to eliminate partisanship and patronage when he ejected Liberal senators from his caucus last winter. 

Tim Uppal, minister of state for multiculturalism, said the Conservative government's position remains that abolishing the Senate should only be done if reform is not possible — but emphasized the top court's ruling leaves the decision with the provinces.

Mulcair said he plans to align himself with those who have spoken out in favour of abolition, such as Saskatchewan Premier Brad Wall, to achieve the goal "Canadians from coast to coast to coast" share.

"Of course the old time parties — the Liberals and the Conservatives, who see this as an unlimited trough from which they can withdraw public money, from which they can get workers for their election campaigns — they're going to try to fight to keep the Senate," Mulcair said.

A spokesperson in the office of Ontario Premier Kathleen Wynne said that while the "Senate plays a valuable role as a chamber of sober second thought," the province would be willing to participate in discussions on how to reform the institution within that function.

"Ontario is ready to participate if the federal government decides to lead collaborative pan-Canadian discussions about Senate reform."

Audit of MP expenses?

Trudeau said Auditor General Michael Ferguson should sit down with the leaders in the House of Commons to share the many lessons he learned during his two-year review — and maybe even launch an audit of the expenses of MPs.

"We will work with the auditor general to do what is necessary. He has already learned a tremendous amount. Maybe it's a matter of adapting our procedures, maybe it's a question of diving into the expenses of the 308 MPs," he said.

"Maybe it's a matter of adapting our procedures, maybe it's a question of diving into the expenses of the 308 MPs." - Liberal Leader Justin Trudeau

Though Mulcair also threw support behind an audit of MPs, Prime Minister Stephen Harper's parliamentary secretary, Paul Calandra, said he doesn't support the idea.

"I certainly wouldn't support that. I think the auditor general made very clear comments that it wasn't required," Calandra said.

But Wednesday evening, the prime minister's office emailed CBC News with a clarification. 

"We support having the auditor general sit down with the board of internal economy and determining a way for him to engage on this," wrote spokeswoman Catherine Loubier.

Ferguson said yesterday that MPs could learn from his comprehensive audit of senators without being subjected to the lengthy — and expensive — process. Ferguson said Tuesday his audit of 116 current and former senators will cost about $23.5 million by the time all is done.

with files from CP