Canadian prime ministers tend to be bland – maniacally so.

Our longest-serving, William Lyon Mackenzie King – who led the young nation through the crucible of the Second World War – is the type and symbol. In his youth, he would walk the streets night after night, hunting for prostitutes – and exhorting them, apparently quite genuinely, to find redemption in the Lord. Later, in the privacy of the prime ministerial mansion, he held séances to consult on affairs of state with his departed mother. He also contacted his dead dog, but there is no record of the pooch offering political advice. All this emerged only after he had joined his invisible councillors. In his lifetime, he presented himself, with unrivalled electoral success, as a cautious and transcendently boring little fat man, who did not look well in a homburg.

Current prime minister Stephen Harper owes his career to this tradition of deceptive mediocrity, which he has elevated to a diffidently shining perfection.

He managed to win, if not the throbbing hearts of voters, at least their shrugging shoulders, only after two consecutive minority governments, during which he and the fractious opposition parties together proved him to be triumphantly faute de mieux. As leader, he has run his party with Bolshevik efficiency – hammering a caucus perhaps a bit over-laden, by historical standards, with yokels, whackos and chancers, into a wide-eyed, tight-lipped regiment of skittish yes-people. Yet with his John Major glasses, his middle-class waistline – neither too working-class wide, nor too patrician trim – his manner of a competent but slightly distracted chiropodist, and the support of a shrewdly distributed not-quite-40% of Canadian voters, he has projected throughout the first two years an air of quiet managerial competence.

And then came Rob Ford. Officially, Stephen Harper has nothing to do with Rob Ford, who, as the world now knows, is mayor of Toronto, and reportedly can be seen smoking crack in a video no one can see. Ford is a conservative, yes, but overt party politics are banned from Ontario's municipal governments, by provincial law. The styles of the two men could not be more different – Ford's emotional careering from sulkiness to rage could not look more different, on TV at least, from Harper's gently superior thin-lipped smile.

But again, there is a video – though yet again, few have seen it. It was taken in Rob Ford's mum's backyard two summers ago, during a barbecue party in honour of federal Finance Minister Jim Flaherty, whose riding is in Toronto's eastern suburbs. The videographer was an unknown conservative stalwart, thrilled to record the surprise appearance of the prime minister himself.

Harper's brief remarks to the delighted backyard crowd contain two somewhat awkward revelations. The first was that he and Rob Ford had become fishing buddies – a condition of some intimacy in Canadian politics.

The second was his appreciation of the political situation:

"We've started cleaning up the left-wing mess federally in this area – Rob's doing it municipally – and now we've got to complete the hat trick, and do it provincially as well."

The "hat trick" line carries the two men's relationship beyond intimacy, into a unity of purpose, a joint political identity. This implication was not lost on the prime minister's office, which within 48 hours had the loyal videographer take it off YouTube – nor on the anti-Harper legions, who put it back up again, where it is beginning to attract renewed media attention.

Getting too close to Rob Ford – or being seen to be – was noxious enough in 2011. Today it's downright poisonous, especially given the prime minister's own current political travails. These take the form of an all-too-typical alleged expenses scandal on the part of Harper-appointed(-for-life) senators – spectacularly compounded by the fact that the most egregious offender, after promising to repay the misappropriated money, was quietly slipped $90,000 by the prime minister's chief of staff in order to do so.

The senator has resigned from the conservative caucus, the chief of staff was sacked, but like some medically-bred super-bacterium, resistant to every political antibiotic in the prime ministerial medicine chest, the infection thrives and spreads. The Royal Canadian Mounted Police are investigating. The senate ethics committee is holding hearings. Harper himself is back from overseas to face Question Period. And that old video could potentially "contaminate" the conservative's whole future in Ontario, in the words of a recent Toronto Star story, achieving a kind of negative hat trick – municipal, federal and provincial.

Will Rob Ford's meltdown link up to Stephen Harper's? Will the public follow the PM's own analysis and recognize a shared political identity between him and Rob Ford? Will they perceive that identity as extending to the same appalling contempt for democratic norms and political integrity? Or will the worldwide uproar over Ford instead drown out any media outrage over the senate scandal? Time will tell.

In the meantime, Stephen Harper is responding to reporters with claims of innocence, founded on the rock of solid ignorance and bland dismissal. It is the Canadian Way. And it just might work again.