This snap election campaign began as a triumphal march by an imperious Prime Minister.  Theresa May entered it almost as more than a mere party politician.  Her Conservative Party had kept hold of its core voters and gained, because of Brexit, permission to be heard among natural Labour ones.  She, Nick Timothy and her core team had crafted an appeal to win these over: an energy price cap, more council homes, new workers’ rights, an industrial strategy.  The polls showed soaring Tory leads.  Little was heard from Labour. Candidates reported from the doorsteps that the contest was a cakewalk.  Britain was set for a Great Patriotic Election.

Team May then made a deliberate decision: to trade off part of this emerging majority for a mandate.  The social contract between the generations is broken in Britain.  Spending on richer older retired people has been protected at the expense of younger poorer working ones.  The former turn out to vote at elections and are the Conservative Party’s base in a country divided less by class than age when it goes to the polls.  David Cameron and George Osborne was wary of offending it.  The Coalition brought in a pensions triple lock, kept Gordon Brown’s winter fuel allowance, and ducked the problem of the rising cost of social care.

This Tory manifesto was made of sterner stuff.  The triple lock has been abandoned.  So has the Cameron-era pledge not to raise VAT, national insurance and income tax.  The winter fuel allowance is to be means-tested.  Above all, the value of the family home is to taken into account when paying for the costs of all social care.  This last proposal was dynamite in a country with a primal attachment to home ownership – and sprung, too, with no notice or preparation.  Its effect on the Conservative campaign is captured by Michael Caine’s famous line from the Italian Job: “You’re only supposed to blow the bloody doors off”.

One can argue that the electoral damage will be deeper in blue seats with expensive houses and big majorities – and that the Tories will simply absorb the consequences today.  But the harm seems to reached further: very crudely, the combined effect of the social care and winter fuel plan seems to have revived a primordial fear of some of those red voters further north (and in Wales): that while Labour gives you money, the Conservatives take it away.  Furthermore, while the Tory manifesto was strong on a national appeal – “Forward Together”, it declares, in Churchillian tones – it was weaker on a retail offer.

This was not a mistake that Jeremy Corbyn and his claque intended to mirror.  While May’s intention is to win a bigger majority today, his isn’t to gain one at all: rather, it is to take a bigger slice of the vote than Ed Miliband gained two years ago, and use the rise to justify staying on as Labour leader.  Corbyn’s manifesto has no national appeal at all – unless one is to confuse this with class war – but makes none the less a clear retail offer to natural Labour voters: a higher minimum wage, no more tuition fees, and end to the public sector pay cap.  That swaggering Conservative poll lead fell in one case to a single point.

If having to tear up a major policy mid-campaign is one’s measure, then this has been the worst Tory campaign in modern history.  The air war never quite got back on track.  Part of the reason for this has been the impact of two terror atrocities.  One might have thought that May would have gained visible support in their wake. Instead, a media that long ago wrote Corybn off went for her jugular, projecting Labour’s attack on her record over police numbers.  Ducking a TV debate that Corbyn decided to turn up to probably didn’t help.  The Labour leader travels light on numbers and dodges the awkward questions: none the less, he has had a good campaign.

Why, then, do the Steve Fishers and Matt Singhs and Chris Hanrettys and Ian Warrens agree that the Conservatives will win comfortably today?  These are experts – apologies to Michael Gove – with impressive records: for example, Singh called 2015 right.  His central projection is a Tory majority of 98.  Hanratty says 100.  Warren has gone for 124.  Even YouGov has thrown in the towel today, and adjusted its methodology: it now gives May a seven point lead.  Part of the reason is turnout expectation.  Another part is that even if younger people do flock for the polls to back Corbyn, they are likely to do in seats where he is already strong.

Another still, stressed by this site, is that polls tell one only so much when target seats are nearly everything and much of the ground war is invisible.  The effectiveness of the “dark ads” that the Crosby/Messina team are slapping up on Facebook may be exaggerated, but to track the progress of Theresa May’s battlebus, as Newsnight‘s Chris Cook has done, is to see that CCHQ expects a mirror image election – to gain less in the blue south, let alone in London, than in the red-then-purple north.  In one respect at least, the Conservative campaign has gone by the book.  It has gained a big slice of the UKIP vote and kept it. No poll has shown the Tories dip below 40 per cent.

Perhaps the best explanation is the most simple.  Voters face a choice today between the quirkily centrist May and Far Left Corbyn.  Maybe all those experts and all the polls are wrong, and Labour will somehow pull it off today – as Leave did last summer and Trump did in America.  Perhaps Syriza has come to Britain.  But common sense suggests that given a choice between a a Far Left party and a non-Far Right one, the latter will win – especially in a contest which, as Mark Wallace pointed out yesterday, has seen the third party lose ground rather than gain it.  This election has been a shot in the arm for two party politics.

Were Corbyn to gain even 35 per cent of the vote today, and the two big parties to scoop up 80 per cent of the vote between them – but, no, you can work it out for yourself.  These are calculations that the sleeping lion of British public opinion will not have bothered to make.  To those of us gripped by politics, elections are compulsive.  Very many voters, by contrast, reach for the off switch.  Today, the lion blinks, yawns, stretches itself – and is asked to pronounce.  Only last summer, a referendum decided, by a narrow margin, to turn Britain’s post-war settlement on its head, and leave the European Union.  That decision is the backdrop against which this election should be seen.

At the head of one party is May.  She has lost one or two of her political nine lives during this campaign.  Her response to Islamist terror is uncertain.  But, more than any other senior politician, she grasps intuitively the scale of the decision made last year – and understands that, whatever they did last June, voters are resolved to put their best foot forward and make the most of it.  At the head of the other is Corbyn – a man who has dedicated his entire political career cuddling up to Britain’s enemies: the IRA, Galtieri, the Soviet Union.  In Labour’s great industrial heartlands, voters have heard the message.  Now let the lion roar.