This article introduces a dual perspective to the study of mediatization of politics, a political actor-centric and a media actor-centric perspective. It applies both perspectives to a case study of the 2015 UK General Election campaign. The media actor-centric perspective focuses on push forces of mediatization, manifested in proactive, interventionist reporting methods. The political actor-centric perspective focuses on pull forces of mediatization, referring to how candidates and parties purposefully draw media logic into the political world in order to achieve better their campaign goals. We argue that the Conservative Party and Labour Party, when exposed to equal push forces, employed different pull strategies in the 2015 UK General Election Campaign. The article uses a set of five indicators to recognize push forces that focus on the style of questions used by journalists when interrogating politicians on TV election programmes (reflecting media actor-centric mediatization). It finds clear indications of assertiveness, adversarialism and accountability in the news approach of the BBC. To recognize pull forces, the article uses a set of seven indicators developed from the literature on campaign professionalism (reflecting political actor-centric mediatization) and finds a considerable imbalance in the effective use of pull strategies between the Conservative and Labour Parties. This latter point leads to what we call lop-sided mediatization. The concluding section discusses inplications for mediatization research in times of Brexit and Trumpism.