If the Tories don't win big in the U.K. election, the knives might come out for Theresa May: Andrew MacDougall

Good political outcomes rely on careful expectation management, and so when British Conservatives lauded Theresa May as the second coming of Christ in the run up to Britain's election, it was inevitable she would go on to disappoint.

But few expected her to disappoint this much, to the point that Labour's Jeremy Corbyn, a bloke who looks and sounds a bit like (an aged) Christ, has now crept to within a few points of May on the eve of the British vote.

At the start of the campaign a short seven weeks ago the Conservatives were 20 points clear of Labour and the talk was of a 100+ seat majority, up from the Tories' working majority of 17 at the dissolution of Parliament. Even better, May's personal numbers ran miles ahead of Corbyn's, invoking dreams of a stonking majority like that won by Margaret Thatcher in 1983.

Alas, all talk of a Iron Lady-like landslide ended weeks ago. And while Conservatives are quietly confident they will return to the Commons with a working majority, that it's even in doubt demonstrates how disastrous May's campaign has been.

'Strong and stable' to 'weak and wobbly'

Prior to the campaign, May was perceived as steely, honest and competent, a reflection of her relatively peaceful six-year tenure at the Home Office overseeing the nation's security. "Strong and stable government" the Tory slogan perfectly captured the conventional wisdom on May.

May was a leader, a uniter and hey, did she just make that bottle of wine appear?

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If there were any Tory concerns at the time, they were overwhelmed by the public's poor perception of Corbyn, whose shock victory in the Labour leadership race in September 2015 had been followed by months of internecine war, with Labour MPs trying and failing to unseat Corbyn last summer. Corbyn's far-left policy and past pallingaround with IRA and Hamas leaders were feared too radical for middle England by Blair-era Labour MPs.

Things had scarcely improved for Labour by spring, and so when the poll margin crept to 20 points in April, the election trap was sprung, framed as a contest between May and Corbyn, competence vs. chaos.

May's flip-flops

To get the contestshe craved, May first had to cave on a promise she had repeatedly made to voters: that she wouldn't call an early election. Tory strategists thought she would be pardoned, provided they could get the message out that a fresh (and larger) mandate would empower May to deliver the strong Brexit the country needed.

The Tory message did get out, but it was unhelpfully paired with the idea that "steady" May went back on her word. This flip-flop came after a humiliating retreat on a budget tax change a few weeks earlier, which, when taken together, hinted at a leader who was "weak and wobbly" under pressure.

Then it got worse: May was forced to backpedal on a key pledge to reform the funding of social care when it became clear the reform would penalize suffers of chronic disease while sparing those who died suddenly. The policy dubbed a "dementia tax"by the press raised the ire of Conservative MPs, including the health secretary, who wasn'tconsulted. May's numbers went into a dive.

And it got even worse: an explosion in Manchester.The interjection of terrorism into the campaign should have played to May's strengths. As Home Secretary, she knew the lengths to whichsecurity services fought to keep Britons safe. But a second attack less than two weeks later in London suggested the system was failing.May, who presided over the system for years, shouldered theblame, and once again a perceived strength her dependable record in government had morphed into failure. The polls weretightening like a noose around May's political future.

Corbynstarts to rise

While May floundered, Corbyn began exceeding expectations. He started his campaign in safe Labour seats, building up his confidence for the campaign's later battles.

An avowedly left-wing manifesto promising tax hikes and fewer privatizations went over well with a population sick of years of Tory austerity. It didn't matter if the sums didn't add up, voters were happy to once again be hearing talk of carrots after years of sticks.

Slowly, the prickly Corbyn, target of the "Tory" press, was replaced by a Corbyn comfortable in his own skin. Even Corbyn's detractors from the moderate wing of the Labour Party admit he has run a good campaign. By keeping the focus on May and her failures, and by connecting demonstrably with voters in full view of the cameras which May with her tightly-scripted campaign bubble would not do Corbyn (somewhat) neutralized his image as a bumbling incompetent. Corbyn's positivity even managed to deflect most of the Tory mud thrown his way.

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On the eve of the election,Corbynis within points of May, depending on the poll. It might all be a mirage, with May sailing home comfortably, but Corbyn has virtually ended talk of his replacement following the vote. The same can't be said, however, for May. The status quo is no longer good enough; if she does not significantly increase her majority, the knives will be out.