Where is population in “surplus population”?

Is the impetus toward “surplus population” in Marx's analysis an effect of capital's law of accumulation or a “function” of it? How might a Marxist analysis of “surplus population” aid in theorizing demographic change under the capitalist mode of production? And to what extent are individuals who lack a “proper job” superfluous to capital accumulation? This article engages these questions through a survey of Marxist and marxisant attempts to theorize the exclusion of certain populations from capitalist employment. The way in which these questions are answered—the way, that is, in which “excluded” populations are understood to relate to processes of capital accumulation—has implications for thinking through appropriate political responses.