A message pings on my phone from a swing voter. This person was a remainer who accepted the referendum verdict, backed Theresa May in 2017, loathes Boris Johnson and thinks Jeremy Corbyn would ruin the country. The Liberal Democrats don’t appeal and can’t win locally. What to do?

It is a commonplace dilemma, hardly worth sharing, except for the detail that this individual was a Tory cabinet minister not long ago. Something peculiar is going on with political identities when people who have served in government for the two biggest parties are at a loss as to how to vote.

The Tories and Labour will continue to dominate English politics. They have the biggest campaign machines, and blue and red rosettes exert strong traditional gravity. But the public has also sniffed out something unfamiliar about their old parties, something pungent, a sweaty kind of mania. There is a new, wild glint about the eyes that provokes unease in the non-aligned citizen.

The nerds who monitor reshuffles as if they were football transfer windows relish an election. It is our world cup

Most people are not party members. Only the eccentric few follow every twist of the debate. The nerds who monitor cabinet reshuffles as if they were football transfer windows relish an election. It is our world cup. But the rest see it more like a trip to the dentist, necessary but unwelcome. It is something that should happen regularly but not often; definitely not recreational. Those are the people who decide the result and, hard though it may be for the obsessives like me to accept, their perspective is often better than ours. Veteran campaigners know to respect the views of people who see politics out of the corner of their eye.

The indigenous politicos of Westminster have already worked themselves into a frenzy, but millions of people are only just beginning to notice the election. I tagged along with a candidate in a leafy ward of Birmingham over the weekend and actual leaves – specifically the council’s failure to sweep them up – were a much bigger issue on the doorstep than leaving the EU. When notified that an election was coming, no one was happy about the news. We did, after all, have one quite recently.

Anyone who has tried canvassing on a chilly November afternoon knows that political campaigns are an intrusion of public argument into private lives. That is why Johnson prefaces every speech with the claim that he does not want an election. He says it has been forced on him by an obstructive parliament. The Conservatives are traumatised by the loss of their majority in 2017. The postmortem on that campaign found many causes of death, and reaction against the perceived opportunism of holding the ballot at all was among them.

Play Video 0:50 Jeremy Corbyn: Trump-Farage-Johnson pact would threaten rights in UK - video

Theresa May had previously ruled out a ballot because she wanted to get on with governing. That matched her image as a grownup prime minister, and having no election suited most people just fine. It was only a year after the referendum, which had felt like pulling teeth. The unravelling of May’s brand began the moment she got greedy and tried to cash in her polling lead. It smelled wrong.

Some of the 2017 surge in support for Labour must be attributed to Corbyn’s campaign, and some was borrowed votes from Corbyn-sceptic remainers. But there was also an ill-defined but potent sense of collective reaction against Conservative hubris. The prime minister seemed to think she was entitled to victory, and the electorate reminded her who was boss. Party identities played their part, but so did a vaguer cultural tendency to disobedience and bloody-mindedness. Voters do not like to be taken for granted, or have their verdict prematurely allocated to one column or another. That human impulse to independence is lost on the would-be architects of electoral pacts and designers of tactical voting websites. That doesn’t mean seat-by-seat collusion is irrelevant, but I suspect its value is overstated.

Nigel Farage’s decision to withdraw Brexit party candidates from seats where the Tories are incumbent sends mixed national signals. It authenticates the prime minister as a Eurosceptic ultra, but that reinforces the feeling among ex-Tory remainers that Johnson’s party is dead to them. And without a Brexit party candidate on the ballot, some leavers will default back to a lifelong habit of voting for Labour, sooner than endorse a Conservative.

Choreography on the remain side is even messier. Even in the seats where pacts have been agreed between Lib Dems, Greens and Plaid Cymru, voters cannot be relied on to take dictation from on high. There are radical leftwing Greens who would rather switch to Labour (not actually a remain party) if their own candidate isn’t listed.

As for the notion that Labour and Lib Dems should come to a grand accommodation, it is as old as it is infertile. They are old rivals from different traditions with grudges at every level from the Commons chamber to council by-election.

Even if individuals in certain seats could set bygones aside, at national level Jo Swinson needs support from liberal Tories who abhor Corbynism every bit as much as Brexit nationalism. Swinson cannot afford to give the faintest hint of formal collaboration with Labour under its current leader. Besides, there would be scant reciprocation. When Labour activists call for an alliance, what they tend to mean is that the Lib Dems should admit the folly of their existence, shut up and dock with the big red mothership of all political virtue. It is not as persuasive a pitch as some on the left seem to think.

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The ambition for pacts comes from the belief that this election is a referendum in disguise, and that voters must be channelled into leave and remain streams before they can be let loose in a polling booth. That isn’t how most people will see things, because it isn’t how general elections work. They are a tangle of old habits and first-time departures, local cultures and personal priorities, of which Brexit is only one. For some it is the NHS, or crime, or just a nasty taste in the mouth when Johnson or Corbyn appear on television – which is as valid a test as any, frustrating though it can be for people who wish the electorate could be organised into tidy ideological compartments. There is latent wisdom in the inattentive majority, the ones whose antennae are just starting to crackle with reluctant political engagement. They haven’t decided what the question will be on 12 December, let alone what answer to give.

• Rafael Behr is a Guardian columnist