With an election looming within nine months, Mulcair and his MPs are gathering for two days, starting Thursday, to plot strategy.
The meeting comes as plunging oil prices and the resulting drops in tax revenues have economists warning about potential problems for both federal and provincial governments.
Insiders say the strategy sessions will focus on what the NDP sees as two myths fostered by Prime Minister Stephen Harper's Conservatives.
One: that the Conservatives are prudent fiscal managers dedicated to economic growth and job creation and on the road to a budget surplus in the coming fiscal year.
Two: that a reckless, big-spending NDP government would ruin the progress that's been made, raise taxes and plunge the country back into deficit.
A perceived lack of economic expertise has long been an Achilles heel for the NDP, which has never formed a federal government.
However, New Democrats like to boast that provincial NDP governments have typically been the most fiscally prudent.
Mulcair is scheduled to kick off the two-day caucus retreat with a speech that is expected to shed some light on his economic policy.
And on Friday the gathering will hear from Kevin Page, the former parliamentary budget officer, who is expected to offer a harsh critique of the Harper government's fiscal record.
Mulcair has been unveiling planks for the NDP election platform since the fall, including a national program to provide 1 million daycare spaces, at a cost of $5 billion a year once it's fully operational. He's also pledged to restore the annual six-per-cent increase in health-care transfers to the provinces, which could drain an additional $36 billion out of federal coffers.
He has been less precise about how he'd pay for his proposals, other than promising to roll back some of the corporate tax cuts implemented by the Harper government.
The collapse of oil prices has made it more difficult for any of the parties to firmly predict how much money they'll have to play with in crafting their election platforms. Some economists already doubt that Harper can keep his promise to balance the books in the coming fiscal year, predicting the loss of oil revenue will keep the federal government in the red for as much as another two years.
However, Finance Minister Joe Oliver has insisted the government is on track to a small surplus next year — most of which has already been earmarked for a series of family tax benefits.
The Conservatives have put opposition parties in a position where they'll likely have to scrap some of those tax cuts in order to afford their own proposed programs — thereby reinforcing the Tory argument that they're reckless tax-and-spenders.
Liberal Leader Justin Trudeau has said he would kill the recently announced measure to allow couples with young children to split their income for tax purposes, a measure he says helps only the top 15 per cent of families.
Mulcair is also adamantly opposed to income-splitting, but has yet to specifically say he'd roll back the Tory measure.
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