David Cameron is pursuing his interest in fish markets; Ed Miliband and Nick Clegg have been acting up about Gaza. Where is Nigel Farage? After Ukip’s spectacular showing in May’s local and European elections, one might have expected it to leap into a frantic summer. Instead, it has gone quiet, feeding an uneasy sense – outside Scotland anyway – of politics unexpectedly returning to normal.

As holidays are taken and the inane rituals of party conferences loom, too many politicians and commentators seem to have fallen for a comfy bit of groupthink: that what with the odd poor poll showing and this sudden outbreak of silence, the menace has receded and we have passed “peak Ukip”. In other words, to quote the wisdom of four-year-olds and people on bad acid, if they can’t see the monster, the monster can’t see them.

“We’re consolidating,” a Ukip high-up assures me. Farage has a new “front bench”, comprising 12 men and five women – all “spokesmen” – who are busy getting on top of their briefs; the domination of the news by horrors overseas (“Other people’s wars – ghastly as they are”) means Ukip is bound to stand to one side. “We’d be foolish to pretend we know more than we do,” he says. What he’s keen to emphasise is the level of grassroots “grunt work” going on, which is embedding Ukip in no end of council wards and parliamentary seats, and cementing its bond with voters.

Meanwhile, a party whose apex of power is control of a town council 13 miles outside Peterborough continues to pull mainstream politics squarely in its direction. Cameron announces new migration measures that will “put Britain first”. Boris Johnson trails his quest to return to the Commons – and obviously to become Tory leader – with the specious claim that the UK could have a “great and glorious future” outside the EU. Only four months ago, Clegg presented himself as a principled avenger come to chop down Ukip’s nasty populism; now he calls for new controls on migration from EU countries and announces the end of subsidised translation for passports and driving licences. Maybe that’s what the prime minister would call “muscular liberalism”; perhaps it actually demonstrates that the Liberal Democrats are led by an absolute chancer.

Judging by recent pronouncements from Rachel Reeves and Ed Balls about immigration, some Labour people recognise the threat from Ukip and are minded to try and do something about it. Others are said to be clinging on to the idea that Ukip remains a convenient means of taking votes from the Tories (witness the surreally complacent words of the Labour frontbencher Angela Eagle: “I’m not as worried as some might be about Ukip’s appeal to Labour voters. I do think it will be interesting to see how much of the Tory vote Ukip eats into though, particularly in those areas where they are contending [sic] in the south-east and south-west”). This looks like a deluded bolt-on to the “35% strategy” whereby Miliband will supposedly sweep into Downing Street thanks to Labour’s core vote and disaffected former Lib Dem supporters; it only compounds the sense that people at the top of the Labour party are lost in the psephological woods.

The truth is that Labour has a Ukip problem that is not about to go away. Last month, polling by the Tory troublemaker Lord Ashcroft suggested Ukip is now the most popular party in two key constituencies: Tory-held Thurrock, which is Labour’s number two target seat, and South Thanet, the Conservative constituency where Farage is said to fancy his chances. “Ukip’s national vote share is not the most useful guide to their prospects at the election,” Ashcroft warned. “Localised Ukip performance could scupper Labour’s chances in seats that Ed Miliband might otherwise hope to take.”

Moreover, Ashcroft’s research proved that Ukip’s claim that it has learned the art of pavement politics from the Lib Dems is now a reality and, with councillors on the ground and a drilled core of activists, it is making hay.

This week the dependably insightful academic, Matthew Goodwin published research based on results from the May elections and census data, which fed into a list of another five seats where Labour ought to be concerned about Ukip, the safest of which is held on a mere 3.9% majority. These are places where next year’s election could be decided.

And that is not all: Goodwin also looked at the prospect of Labour winning power in 2015 (by a whisker surely), a belief among Ukip activists that the inevitable mid-term backlash could spark a “serious rebellion”, and possible dividends for Ukip in a long list of Labour strongholds: Bootle, Bolsover, Doncaster, Hartlepool, South Shields, Stoke-on-Trent – even treasured seats in the south Welsh valleys.

So what is to be done? As with Cameron and Clegg, Balls and Reeves evidently think the solution is to fixate on immigration numbers and benefit entitlements, and affect to sympathise with Ukip voters’ fury. The Fabian Society has just published a report that creditably advises Labour to make the case for the EU, but also proposes “restrictions on immigrants claiming benefits for a year or more” and compulsory language lessons for people who are new to the UK.

In doing so, it bumps up against something inescapable: the fact that there are few spectacles less convincing than lefty-liberals affecting to “get tough” on this and that, while actually dying inside. MPs have now been striking such poses for years; so much of the Ukip insurgency is founded on a hardened loathing of professionalised politicians that more of the same will surely only deepen its supporters’ cynicism.

Which brings us to a truth too little heard in modern political commentary: the main parties now gaze at an array of abstainers and newly converted Ukip voters across a divide that will take years to close, if it ever does. In the build-up to the election, some voters may grudgingly return to Labour or the Tories, albeit temporarily. A recent ComRes poll commissioned by the Ukip donor Paul Sykes found that 37% of Ukip voters were “certain” to maintain their support at the election and another 49% were “likely” to do so.

I wouldn’t patronise them by assuming such claims are idle threats; they seem to represent something almost wholly beyond the main parties’ control.

Ukip’s 2014 conference will take place at Doncaster racecourse, chosen because of its proximity to Miliband’s constituency. “We are taking the Ukip message straight into one of Labour’s most neglected heartlands,” says Ukip’s deputy leader, Paul Nuttall. “This event will represent our firing of the starting pistol for the long general election campaign and will give the lie to any idea that we are only a threat to the Tories.” He sounds serious, doesn’t he? Much as it pains me to say so, he has every right.