This article examines political change in the Durham Miners' Association (D.M.A.), one of the best‐established, largest and most influential Edwardian trade unions. It argues that the hitherto ignored rank‐and‐file movements (especially the Durham Forward Movement from May 1912) deserve a central explanatory role in offering new perspectives on the nature and strength of the Independent Labour Party's (I.L.P.) challenge to the Liberal hegemony within the D.M.A. The agency of a new, younger generation of emerging I.L.P. activists, framing an appeal to miners' material interests harnessed to a radical reforming agenda and support for Labour, meant that Labour's prospects in the Durham coalfield by August 1914 were rather more positive than has been recognized.