Analysis of the politics of HIV programme scale-up requires critical attention to the role of the state, since the state formulates HIV policies, provides resources for the HIV response and negotiates donor involvement in HIV programmes. However, conceptual and methodological approaches to analysing states' responses to HIV remain underdeveloped. Research suggests that differences in states' successes in HIV programme scale-up reflect their levels of 'political commitment' to responding to HIV. Few empirical measures of political commitment exist, and those that do, notably the AIDS Program Effort Index (API), employ ad hoc scoring approaches to combine information from different variables into an index of commitment. The indices are thus difficult to interpret and may not have empirically useful meaning. In this paper, we apply exploratory factor analysis to examine whether, and how, selected variables that comprise the API score reflect previously theorised dimensions of political commitment. We investigate how variables associated with each of the factors identified in the analyses correspond to these theorised dimensions as well as to API categories. Finally, we discuss potential uses--such as political benchmarking and accountability--and challenges of factor analysis as a means to identify and measure states' political commitment to respond to HIV.