Amongst the fall-out from the astonishing performance of UKIP on Thursday in the Heywood and Middleton by-election, it is possible to pick out a theme that is becoming more and more important as the election approaches. UKIP constantly points at the “out-of-touch” political elite that they are targeting and from whom they offer an alternative. Even though much of their alternative is socially divisive and economically sclerotic, they are right when they talk about the “Westminster bubble” that too many politicians live in.

Owen Jones – in an excellent article for the Guardian today – mentions that “in 1979, 21 MPs previously worked in politics, but in 2010, the figure had reached 90. One in eight MPs elected in 2010 previously worked as private consultants, a jump from one in 25 in 1997”. This disconnect between the public and politicians – in which politicians simply haven’t lived the life of those they lead, has led to a disconnect between what politicians think they should talk about, and what the electorate want them to talk about.

In Heywood and Middleton, for example, much of the Labour Party’s campaign was about the NHS. The candidate had worked for the NHS, and much of the campaign literature and Ed Miliband’s speeches when he visited were about the NHS. Labour have become convinced that the NHS is a vote winner, so they talk about it. How they will protect it, how the Tories will destroy it. This led David Cameron to talk about the NHS in his conference speech and make another economically dangerous promise to ringfence the NHS budget regardless of the consequences on other departments. This suggests the Conservatives also think the NHS is vital too. Given it is the third biggest employer in the world – when you work in Westminster it must seem like a no-brainer that the NHS is a massive voting issue.

Yet the voters of Heywood and Middleton didn’t want to know about the NHS. Yes, of course they would rather it is there as a safety net. But the NHS won’t put food on their table. The NHS won’t give them the dignity of a properly paid job. The NHS won’t put a roof over their head. Does Ed Miliband realise that talking about a cost-of-living crisis whilst ignoring the effect of immigration pushing down wages is contradictory? UKIP got the votes they did because they are addressing issues that the public not only care about, but will also vote on.

In a seminal study of voting behaviour in the UK, the academics Butler and Stokes argued that for an issue to be “salient” (something that would actually affect a person’s vote – 1) Voters must be aware of issue 2) Voters must have an opinion on an issue 3) Voters must detect a difference between parties on the issue 4) Voters must actually convert their preference into actually voting for the party whose views on the issues approximate to their own.

It looks like the NHS may possibly meet the first three criteria, but not the fourth. But at the moment, in many UKIP target seats the fourth is immigration and the economy. If the main political parties don’t address these (and let’s not forget it was those that Ed Miliband forgot in his speech) then they may find themselves sharing the House of Commons benches with quite a lot of UKIP MPs next May.