The standard explanation for the choice of electoral institutions, building on Rokkan’s seminal work, is that proportional representation (PR) was adopted by a divided right to defend its class interests against a rising left. But new evidence shows that PR strengthens the left and redistribution, and we argue the standard view is wrong historically, analytically, and empirically. We offer a radically different explanation. Integrating two opposed interpretations of PR—minimum winning coalitions versus consensus—we propose that the right adopted PR when their support for consensual regulatory frameworks, especially those of labor markets and skill formation where co-specific investments were important, outweighed their opposition to the redistributive consequences; this occurred in countries with previously densely organized local economies. In countries with adversarial industrial relations, and weak coordination of business and unions, keeping majoritarian institutions helped contain the left. This explains the close association between current varieties of capitalism and electoral institutions, and why they persist over time.