Issue ownership theory offers an explanation of why parties and candidates focus on certain issues in campaigns. We propose a measure that focuses on changes in public perceptions of relative party issue strengths and weaknesses that persist over at least two election cycles. Using this measure, we identify more than thirty cases of issue ownership loss or gain for the major parties in the U.S., U.K, Australia and Germany over a period between 1970 and 2013. Drawing on a range of contextual data in the histories of each country, we then test a theory of ownership change based on a combination of salience, performance and policy factors. The implications are important for theories of party competition and public opinion and for our understanding of elections.
