“The core of the Prime Minister’s argument is that people cannot reasonably expect the taxpayer to pick up the bill for their social care when they can help meet some of it with money locked up their homes. She is right.  But this is a hazardous political enterprise, and may well have an effect on this election.  Some, perhaps many, Tory voters will vote yellow or purple in protest – or simply not vote at all.”

So ConservativeHome wrote on Friday as we praised Theresa May for pursuing Grown-Up Government, while warning that many voters will be unwilling to “put away childish things”.

And so today’s polls suggest.

YouGov for the Sunday Times puts the Conservatives down to 44 per cent, with Labour up to 35 per cent. That’s the smallest Tory poll lead that it has found this year.

Survation for the Mail on Sunday shows the Conservatives on 46 per cent and Labour on 34 per cent.

Polls come and polls go, but these have undoubtedly picked up a sense of protest about, in ascending order, May’s proposed junking of the pensions triple lock, means-testing the winter fuel payment, and her social care plan.

John Rentoul asks in his Independent column today why May spelt that last policy out in some detail. Perhaps the answer is in order to ensure that she gains a mandate to get it through the Lords.

At any rate, the election can now take one of two courses.

First, the social care proposals come to dominate the election, scaling back May’s projected majority or, just possibly, delivering a hung Parliament.

Second, Lynton Crosby – perhaps this week, or perhaps next, after the Bank Holiday – lets slip the dogs of war on Jeremy Corbyn on defence, immigration and, above all, Brexit. And the Tory position rallies.

The second outcome is the more likely.  May seems to have calculated that it is worth weakening her majority to strengthen her mandate – in other words, risk losing some votes on June 8 in order to deliver the policies she wants later.

And the way in which her support is distributed probably helps her.  The number of people who would lose from her social care plan falls, broadly speaking, the further one leaves the greater South-East behind.

So May’s calculation will be that it is worth shedding some Conservative votes in her southern heartlands in order to pick up some Labour ones in northern marginals.

Furthermore, a poll wobble now is not unhelpful to Downing Street and CCHQ.

As Harry Phibbs wrote yesterday on this site, the biggest threat to a Tory landslide is the expectation of a Conservative landslide – leaving Tory voters convinced that since May will win anyway, there’s no point in turning out to vote.

Polls like today’s are likely, if repeated, to stir a panic stampede in the centre-right press (now even more onside than  before, given May’s pledge to drop Leveson Two) and among Tory voters.  That would solve any abstention problem.

None the less, that the issue of postal votes has followed the launch of the Conservative manifesto so swiftly will do nothing to help the Party’s re-election prospects.

And Labour’s ratings have been steadily rising during this campaign.  The polls may simply be overstating the party’s support yet again, a real weakness of theirs in recent years.

But it is also likely that, precisely as ConservativeHome said in the wake of its launch, Corbyn’s red manifesto has helped to shore up his core vote – which, since he is fighting to keep control of the party after the election, is the document’s real purpose.