I've asked this question before and I to find it interesting. Certainly here in Scotland the vast bulk of folk performers do seem to be left wing and also a substantial majority seem to be quite pro-independence too. Not sure if those type of leaning people are drawn to folk music or if people are swayed by their contempories once in the folk world. I know there are exceptions but from experience the bulk, whether Scots born or English incomers, are left leaning pro-independence supporters. Much more so than the regular audiences in local clubs who are much more mixed and seem to have a far higher percentage of unionists! No scientific stats behind that just experience as it has been openly discussed for several years now!