Last year, the UKIP annual conference was held in Westminster. This was supposed to be a smart move – ensuring the presence of a London-based media that might not otherwise be bothered to attend. In the event, what it did was ensure maximum coverage for the antics of Godfrey Bloom.

This year the purples are going to Doncaster – and not just because it’s a long way from London. The South Yorkshire town is emblematic of the sort of places in which UKIP is emerging as a serious threat to Labour.

Matthew Goodwin and Caitlin Milazzo explore this phenomenon in a fascinating piece for the Guardian:

“The 2014 election results were certainly a wake-up call for those who refused to believe that Ukip could inflict mass damage in Labour territory. The party that some progressives cheered on as a tool for ‘dividing the right’ took over 41% in Rotherham and North East Lincolnshire, over 35% in Doncaster, Hartlepool, Middlesbrough, Scarborough, Redcar and Cleveland and Kingston-upon-Hull, and over 25% in places like Carlisle, Calderdale and Stockport.”

Indeed, UKIP is in the process of capturing whole sections of Labour’s core vote:

“Between 2005 and 2013 Labour support among white working-class pensioners slumped from 45% to just 26%. In the same period, Ukip support among this group surged almost tenfold, from 3% to 28%.”

This could just be the start – which is why nothing would suit Nigel Farage better than a Labour majority at the next election:

“…some inside Ukip… talk of a ‘2020 strategy’ for establishing their party as the only long-term credible alternative in Labour heartlands. ‘This seat is not for 2015,’ explained one senior activist to us while flicking through a list of Ukip’s targets. ‘It’s for 2020 when the incumbent Labour government is on its knees.’”

Goodwin and Milazzo go on to argue that having taken too long to wake-up to the UKIP threat, Labour is now bungling its response. Despite the very strong evidence that red-to-purple switchers are primarily motivated by cultural issues such as immigration, national sovereignty and same sex marriage, Labour’s counter-attack has focused on economic issues:

“Last month Labour sought to frame a vote for Ukip as one for a Thatcherite party that would raise taxes, force voters to pay to use the NHS and see their local GP. Such a response is not surprising; it is rooted in the old Marxist belief that support for nationalist parties is driven by economic insecurity, and encouraged by capitalists who would prefer ethnic over class conflict.”

There’s a great deal of truth in this, but the Marxist influence on Labour thinking goes a long way back – certainly back to the days when ‘Old Labour’ had no difficulty in appealing to the cultural sensibilities of its working class supporters. What, then, has changed?

A clue is provided by another piece in the Guardian, in which Rowenna Mason and Aisha Gani look at the backgrounds of party candidates in winnable seats.  They report that while 17% of the Conservative candidates “have links to Westminster as former special advisers, party workers, researchers, lobbyists or MPs,” the figure for Labour is remarkable 54%. And that’s not the end of it:

“There are also 15 Labour ex-MPs standing again, having already been ousted once by the electorate – one in five of those fighting the most marginal seats. These include some who were heavily criticised over their expenses arrangements before the last election…

“Four Labour candidates in winnable seats are also related to former politicians.”

Thus it is the Labour Party – the Labour Party – that is now the most obvious example of Westminster politics as a lifelong, graduate-only profession.

Even worse, Labour’s institutional uniformity facilitates ideological conformity – because the narrowness of outlook that already distinguishes the party can be reinforced at every stage of career development.

One might object that sharp differences of opinion can be found in all the major parties – including Labour. However, the question is whether these differences actually matter. In this respect, one needs to apply what I call the Next Leader Test. No one can be sure who the next leader of each party will be, but in Labour’s case you can be sure what his or her position will be on just about any issue. Whether it’s on Europe, immigration, the economy, family structure, abortion, environmental matters, free schools or welfare reform – the precise policy details may vary, but the underlying attitudes are utterly predictable.

While all manner of ideological currents swirl about within the Conservative Party – liberal, reactionary, libertarian, Burkean, Thatcherite, you name it; Labour has become the party of exclusive, middle-class, metropolitan values – fundamentally at odds with those of its traditional supporters.