The thing that stops a lot of people actually voting for the Conservatives is what I have called "Toryphobia", the irrational fear of the Conservative Party, a term I don't recall seeing anyone else using, although I can't believe that I have actually made it up myself.
As a former sufferer myself from Toryphobia, I believe I can speak with some authority on it. On my 18th birthday, within the first term of Margaret Thatcher's premiership, when I was naive, idealistic and frankly embarrassingly foolish, I swore 2 things to myself: that I would never sing the National Anthem, and that I would never vote Conservative. Needless to say, the first of these resolutions lasted less than 5 years or so, but it took 20 years for me to summon the courage to break the second. And that is despite being able to admit to myself before I was 25 that, although I didn't like Mrs Thatcher (and I never did reconcile myself to her while she was PM), I would be comfortable with a Conservative Government led by, say, Michael Heseltine (in hindsight, what an excrutiating thought!). Indeed, I effectively voted tactically in both 1987 (SDP-Liberal Alliance) and 1992 (Labour) for the candidate less likely unseat the incumbent Tory MP. It was only when the Conservatives were out of office, at my 5th General Election, after my worldview had changed fundamentally due to co-founding a small business, and consequently ceasing to take the Guardian as an economy measure, that I finally felt able to vote Conservative. Even so, that was primarily in opposition to the Blair Government: despite being slow to adopt political wisdom generally, I was at least quick to see through Blair!
Anyway, the point I am illustrating is that quite of lot people have invested themselves emotionally in being anti-Tory, and it takes quite a considerable effort to turn that around. It is still the case that I don't think I could ever bring myself to actually join the Conservative Party, but that is partly because I value my own independence too much: I don't want to be part of a political tribe.
People really are quite groupish (as explained by Professor Jonathan Haidt in The Righteous Mind) - on the whole, they don't tend evaluate the policies of the parties dispassionately, but make decisions emotionally, and therefore they tend to vote along the same lines as other people they think of as "us". The problem with the Tories, especially those like David Cameron, George Osborne and Boris Johnson, is that to most people they give the impression of being "them".
Working class Somewheres historically have therefore tended to vote Labour for tribal reasons, and have continued doing so out of inertia, even while the Labour Party itself has been captured by Anywheres, and its values have drifted further and further away from its traditional support base. At the last election, however, it seems clear that many Somewheres are no longer prepared to continue to support Labour, but because they are so emotionally invested in Toryphobia, they haven't switched parties, but have simply not voted at all.
Of course, Brexit changes things substantially, and it is becoming clearer to Somewheres that the Anywhere-dominated parties no longer represent them. Along with being led by the Somewhere-friendly Theresa May, does this mean that many will now finally be able to overcome their Toryphobia?
