The question that has been nagging at me is whether Corbyn is the UK's Trump, or the anti-establishment underdog who seizes power when that very establishment sees that outcome both as terrible and highly unlikely.
And then I thought that perhaps I am framing the question incorrectly. The more apt issue is whether Theresa May is Hillary Clinton - namely a professional, thoughtful candidate who fails to connect with important groups of voters.
From the moment she took office last July, she seemed to have identified this danger - because her first act was to reach out to the voting group, those on lower incomes, largely white, who voted to leave the EU and for Trump in the US.
And at the start of the election campaign, she seemed to have built a connection with them, through her emphasis on delivering an efficient Brexit and controlling immigration.
But both of those messages now look messy: she will not say when immigration will fall to tens of thousands; and it is not obvious that the UK's conspicuously fractious relationship with the rest of the EU augurs well for a relatively painless withdrawal.
More seriously, she probably under-estimated how powerful the Leave campaign's claim had been that leaving the EU would deliver a big windfall for investment in public services, especially the NHS.
So her manifesto - with its emphasis on fiscal responsibility, its failure to deliver significant additional sums to stretched schools and hospitals, its abolition of a universal winter fuel allowance and free school meals for the youngest, its raid on the savings of the elderly to pay for social care - well in many ways it was a kick in the teeth for those she had originally sanctified as families who are "just about managing".
They felt spurned. And to their surprise they noticed that a metropolitan leftie, Corbyn - whom they instinctively mistrusted - was promising to spend on schools, childcare, higher education for their kids, hospitals (though actually not so much) and benefits (also not so much).
Suddenly her hopes of winning a swathe of Leave-supporting seats in Labour's former northern heartlands look more heroic than inevitable.
And if YouGov's analysis for the Times is remotely accurate, the thought of her as Union Flag Hillary could become eerily true - with its prediction she could lose her parliamentary majority while picking up many more votes than Corbyn and Labour.
As I have said before, the relentlessly negative and scaremongering nature of her campaign may be necessary for victory, but it does not look to be sufficient for victory.
Negativism alone did not win the referendum for Leave or the White House for Trump. They were victorious because they promised that Britain and America respectively would be more prosperous, more confident and more secure for everyone.
Some will say these were the claims of charlatans, and thank goodness May does not stoop so low.
But after almost a decade of austerity, Britons are seemingly crying out for a bit of optimism and hope. So Corbyn's public-spending splurge, and his relentless cheerfulness even after humiliating himself, are seductive for many.
So the challenge for May in the next week - against the unpromising backdrop of a manifesto that majors on the looming struggles rather than the rewards - is to explain why Britain will be happier and more prosperous under her aegis.
For perhaps the most technocratic political leader the Tories have produced for a generation, she needs to find the vision thing.