Those seeking to influence campaign finance policy often invoke public opinion to support their legal and policy arguments. Thus, an understanding of the factors that explain citizens’ views about the topic can help illuminate the political landscape surrounding it. This study examines the foundations of public opinion about campaign finance issues that emerged in the wake of the 2010 U.S. Supreme Court decision in Citizens United. An analysis of original data from a national survey found that political predispositions — including party identification, political ideology, external political efficacy, trust in corporations, and political interest/attention—predicted individuals’ opinions, as did use of the Fox News cable channel and satirical television news programs. The results speak to how a range of actors may shape and capitalize on the nature of public opinion here.