Liberal MP Marc Garneau was on to something, when he said on his Twitter account: “For [Stephen Harper], if there is positive economic news, he deserves the credit. If the news is bad, it’s the fault of the rest of the world.”

There has been a subtle shift in the Prime Minister’s message track in recent days, from boasting about the Conservative government’s track record on jobs and growth, to blaming Canada’s economic stagnation on the global economy.

Speaking at the weekend, Harper pointed the finger at a first quarter contraction in the U.S., the Greek financial crisis and the Chinese stock market meltdown.

It is a sensible shift — it allows the Conservatives to still talk about their value proposition — their supposed “strong leadership”on the economy, while claiming the scale of the problem defies even their financial wizardry.

For #PMSH : if there is positive economic news, he deserves the credit. If news is bad, it`s the fault of the rest of the World #cdnpoli —

Marc Garneau (@MarcGarneau) July 12, 2015

Joe Oliver, the finance minister, has been road-testing the “fragile global economy” line for a few weeks — not to mention the suggestion that such conditions are not optimal for taking “imprudent risks with inexperienced leadership.”

It has all the hallmarks of a 2008 re-run, when Stéphane Dion was pilloried for being a leader who was not worth the risk. “When you’re running a trillion and a half dollar economy, you don’t get a chance to have do-overs,” Harper said of Dion’s infamous false start interview with CTV, when the-then Liberal leader was asked what he might have done differently on the economy.

A key difference this time around could be that Canadians appear to have an appetite for a change of government and, crucially, little fear about the alternatives.

Voters might buy the line that the problems with the economy are imported but, consequently, they don’t seem to think things would be any worse under a different shade of government.

An Abacus Data poll last week suggested only 30% believe an NDP win would adversely affect economic growth – scarcely more than say they would vote Conservative. The number for the Liberals was similar. Both parties scored well on job creation, infrastructure spending, the environment and even on security. The only area where there was an evident caution was on the opposition parties’ taxation policies.

Having decoupled the economy from government performance, the Conservatives have, inadvertently, taken the sting out of historic fears of NDP competence. At a time when three in four voters say they are interested in changing the government, that is not good news for a ruling party.

If the Conservatives are to be re-elected, they are going to have persuade voters that the economy cannot be run like an airplane on cockpit automation, responding only to semi-annual nudges by the Governor of the Bank of Canada.

Having decoupled the economy from government performance, the Conservatives have, inadvertently, taken the sting out of historic fears of NDP competence

The opposition criticism of the Conservatives is that they have not done enough to stimulate the economy as it has slowed. In fact, the measures announced by the Conservatives will amount to a $10-billion cash injection into the economy this year, in the form of infrastructure spending and family tax cuts.

One big component of that will be felt across the country on July 20, when $3-billion of backdated universal child care benefit cheques start landing in mailboxes (those with children under 6 will get around $520 per child next week; those with kids 6-17 will get $420).

The good news for the Conservatives is that there is still everything to play for. The Abacus poll suggested only 28% of voters have firmly decided where they will mark their ballot.

The Liberals and NDP have not yet made a compelling case why they would be an improvement on Harper on the economy. Both may argue that budget surpluses during a slowdown don’t make sense. The U.K. Chancellor last week delayed a return to balance for another year, in favour of a small but manageable deficit he deemed necessary to fund military spending, corporate tax cuts and a new national living wage. The British economy is, perhaps not coincidentally, growing faster than any of its G7 peers, with employment at record levels and wages rising.

Modest deficit financing may be a good idea from an economists’ perspective, though it could prove toxic politically.

The Conservatives are 10 points down from where they were on polling day in 2011, and the Liberals are 10 points up. The NDP surge was stopped at the gates of Toronto last time, as blue Liberals held their nose and voted for Harper to stop the socialists getting their hands on the keys to the Treasury.

But in a world where voters seem prepared to believe that Canada is a hostage to international economic fortune — not to mention that budgets balance themselves — it is a tactic that may have had its day.

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