What I wonder though, does this culture make it more left wing than a similar, very English town?
Well what would a "similar" English town be? To be at all "similar" it'd still have to be a very working-class place not in sync with its surrounds at all; say the rougher bits of Luton or Slough?
My definition of similar (which could be wrong, I don't know much about Corby) would be like you say working class, completely different from it surroundings, and recently industrial. Perhaps eastern Oxford as well?