Let’s be frank: byelections are rarely significant to anyone other than the people running in them. They almost never move a minority government into majority territory (or vice versa). They’re a decent barometer for the popularity of the government of the day, but, beyond that, they’re of little interest to the general public, the vast majority of which doesn’t bother showing up to vote in them.

But that was not at all the case 50 years ago today, when Ontario’s political establishment was sent reeling by the most unlikely byelection shocker in the province’s history.

Let’s set the scene.

Back in September 1963, Premier John Robarts went to the polls and won a smashing victory for his Progressive Conservatives. The Tory dynasty celebrated its 20th anniversary in power, and the Big Blue Machine appeared to be purring along and in mint condition. In fact, Robarts won the highest proportion of the total vote in post-World War II history — 48.9 per cent. No one’s beaten it since.

Four years later, just three months after Canadians celebrated their Centennial, Robarts went back to the people and won a second consecutive majority government, albeit with fewer seats and less of the total vote. But a majority is a majority, and Ontario was still reliably Tory blue.

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However, midway through Robarts’s second term, many observers noted a kind of ennui setting in. The PCs were approaching their third straight decade in power. Robarts was starting to visibly age and put on weight. The issues still interested him, but the fundraising responsibilities associated with leading the PCs, as well as the internal workings of the party, didn’t. And more and more people could tell.

In February 1969, a backbencher in the Robarts government, Neil Olde, died, necessitating a byelection — the only one during Robarts’s second term. Everyone, and I mean everyone, for a variety of reasons, assumed the Tories would hold Olde’s riding of Middlesex South.

First and foremost, Middlesex South was in the premier’s backyard, just outside London. Second, the Tories had held the riding uninterrupted since 1943. And third, even if the PCs were suffering a bit of midterm blues, it was unimaginable that they’d lose one of their safest seats.

“There was a complacency among the Tories at the time,” recalls Ontario’s 20th premier, David Peterson, who in 1969 had returned to living in London, having recently graduated from the University of Toronto law school. Peterson was still six years away from becoming the Liberal MPP for London Centre. But he remembers the PCs feeling a certain invulnerability at the time, as Robarts and high-ranking party mucky-mucks “gathered in the back of [Fred] Jenkins’s seed store in London to run the province.”

“No one expected us to win,” adds Stephen Lewis, the former United Nations ambassador who, 50 years ago, was a member of the NDP caucus in the Ontario legislature. Lewis emailed me some of his recollections of that campaign, into which he dove head first.

“I took leave of life to manage the Middlesex campaign,” is how he put it.

The NDP’s candidate was Kenneth Bolton, a 63-year-old British-born Anglican priest and married father of five, who was active in the social-justice movement with groups such as Oxfam and Amnesty International. Complicating Bolton’s campaign efforts was the fact that he’d been in a traffic accident three months before byelection day and had broken several bones.

But Bolton had a few other things going for him, starting with the NDP’s playbook. Five years earlier, in the Toronto riding of Riverdale, the NDP’s Jim Renwick had won a shocking victory in another byelection, defeating broadcaster Charles Templeton, who many figured would be the next Ontario Liberal leader.

“We carried the [same] tactics of Riverdale into Middlesex South,” Lewis recalled. “We brought in people from Toronto, Hamilton, and Kitchener, and with Ken as the vanguard, we simply overwhelmed the electorate.”

In addition, Bolton turned out to be a much better and more effective candidate than conventional wisdom figured.

“Everyone wrote him off as some kind of religious relic,” Lewis wrote. “Instead, he knocked on virtually every door in the riding and presented himself as he absolutely was: a kind-hearted gentle soul who just wanted to do good. He cast an innocent spell over all those he met.”

And, finally, Bolton had a historically huge issue lining up in his favour: in 1966, the federal government brought in Medicare and invited the provinces to sign on. Even though the feds would pay half the cost, the Robarts government was resistant. Ontario already had its own provincially run plan that covered almost everyone (many doctors, as a rule, worked pro bono for those who couldn’t afford coverage).

Robarts called Medicare “a Machiavellian scheme” because he was convinced that the federal government would get all the provinces on board and then, over the years, reduce its allocation. (In fact, the premier was absolutely right about that.)

But half a century ago, those chickens hadn’t come home to roost yet. Ontario’s refusal to join the new plan was becoming a sticky political problem for the Robarts government, as Medicare was seen as a very desirable social program. The Middlesex South byelection was becoming a referendum on the province’s handling of the issue. Before they knew it, the New Democrats were surprised to see that voters all over the riding wanted their campaign signs.

“By the end of the campaign, there were so many Bolton election signs in the riding that there was concern that some of the streets would drop below sea level,” Lewis recalled.

Then, on byelection night, the unimaginable happened: the Tories went down in defeat at the hands of Bolton, who won by 1,400 votes. The ramifications were almost instantaneous.

“Robarts was so taken aback by the victory that he enhanced healthcare when the Legislature reconvened,” Lewis says.

Sadly for Bolton, the story doesn’t quite have a storybook ending. Two years later, Robarts was gone, replaced by Bill Davis, who led the PCs to an even bigger majority government in the 1971 general election. Davis took eight seats from the Liberals and one from the Stephen Lewis-led New Democrats. Guess which NDP seat went back into the blue column?

Of course: Middlesex South. And it remained true blue for another 14 years — until a Liberal leader from London named David Peterson helped move it into the red column.

That was the end of Bolton’s political career. He moved to the West Indies to do missionary work. He died of heart failure at the age of 89 during a flight from England to British Columbia in 1996.

His son, also named Kenneth, ran for the NDP in Yukon in the 2008 federal election but came fourth.

Bolton’s byelection victory did not usher in the dawn of a new socialist utopia in Ontario. But it created a shockwave that helped usher in Medicare — and, for that alone, it’s worth remembering 50 years later.

Correction: In an earlier version of this article, David Peterson made reference to "Bill Jenkins's seed store in London." In fact, it was Fred Jenkins who ran the store.