Welcome to an extraordinarily bizarre election day. Pause on the way to the polling station to wonder at the astounding mayhem within our “ruling” party, soliciting votes even while wrenching its leader from Downing Street. We may be so used to the Tory party in meltdown that we forget to be amazed at what is unfolding before our eyes – on election day.

Even allowing for all Andrea Leadsom’s fantastical ambitious absurdities, ponder how astonishing it is to see the leader of the house, no less, resigning on election eve just to steal a march on all her improbable leadership competitors. Jeremy Hunt is marching in to see the prime minister in publicly threatening mode – on election day. Forget any sense of decorum towards their party or their country, or the electoral process.

To be sure, the Tory party has a long history of leadership defenestrations, none more humiliating than Margaret Thatcher’s brutal removal. Ted Heath never recovered from his ruthless rejection by his colleagues. Nights of the long knives and ejections are what Conservatives do in order to renew and survive, the famous men in grey suits ready to step in whenever the good of the party requires it. The party had an entitled right-to-rule discipline that reasserted itself after temporary ructions. The party knew what and who it was for, and how to hold on to power for most of the postwar era, regarding Labour governments as minor aberrations in the long Tory hegemony.

But now, Brexit fever has seized its core, its cabinet, its members and its grey suits. The initial handful of Europe-hating Typhoid Marys have infected a large part of the country with this mortal disease. The few trying to cling to a modicum of sanity are cast as rebels – Philip Hammond warning what no deal will mean; Amber Rudd and Nicky Morgan striving to revive a rose-tinted false memory of one nation Toryism. In its Brexit delirium, the party will choose Boris Johnson, the sociopathic chameleon who is reported to be claiming the one nation ticket even as he spews out crude, membership-pleasing law-and-order columns in the Telegraph.

No gravitas, no dignity – the Conservative party is no longer the British establishment. Adrift from business, the Lords and the established church, the party has pulled up all its anchors, its grassroots rampaging off into the Farage wildwoods. The Brexit project is revolutionary: the “real Brexit” Leadsom claimed last night is an autonomous utopia of “sovereignty”, a self-propelling spinning star of an idea no longer claiming real-world benefits and consequences. Those who have drunk the potion – not just Leadsom but apparently all the candidates for leader – are beyond hearing the Hammond, Rudd and Morgan line of reasoning.

Those who have lived all our lives under the awful inevitability of Tory victories at elections look with astonishment at the latest poll showing them at 7% – yes, 7%! – on this election day.

Here’s the great question: is this party really in a death spiral, or will it always right itself? Conservatism as the British default is so deep-dyed in the national psyche it’s hard to think this is the end. This generation of Conservatives has brought us so low in this decade: in austerity, in stagnant incomes, in devastated public services, catastrophic productivity, lost social security and lost respect abroad. In its visionless hopelessness, the party may indeed have eaten itself. If so, it may be replaced on the right by anti-establishment Faragism, with even more sinister aims in power. Or else the demise of this great pillar of reaction could open doors to a chance of something better.

But it’s easy to be carried away by the traditional turmoil in a free-hit European election whose results may be only a little more extreme than 2014’s. No one knows if old voting habits will be restored under the hammer of first-past-the-post in the general election that is likely later in the year.

For today, all that matters is the final tally of remain v Brexit votes. Will the total of remain votes prove beyond doubt that any Brexit deal without the consent of the people would be a democratic disgrace? That will depend on how the face-both-ways, we’re-not-a-remain-party Labour votes are counted.

History will show the Labour leadership has made a dreadful error – when virtually all its members and the great majority of supporters are remainers. Most Labour people will, rightly, register their vote for a true remain party. Unknowable is whether those angrily fleeing from both main parties today will ever return.

• Polly Toynbee is a Guardian columnist