Dominant theories of legislative organization in the U.S. rest on the notion that the majority party arranges legislative matters to maximize its electoral fortunes. Yet, as we demonstrate in this paper, there is little or no short-term electoral advantage for the majority party in U.S. state legislatures, and there is a pronounced downstream majority-party disadvantage. To establish these findings, we propose a technique for aggregating the results of close elections to obtain "as-if" random variation in majority-party status, allowing us to overcome the central empirical obstacle of selection bias that typically prevents scholars from studying effects of majority-party control. We argue that the results from this approach are consistent with a phenomenon of inter-temporal balancing, which we link to other forms of partisan balancing in U.S. elections. The paper thus necessitates revisions to our theories of legislative organization, offers new arguments for balancing theories, and provides an empirical technique for studying the effects of majority-party status in legislative contexts.