We observe wide variation in the effectiveness of Corporate Political Activities (CPAs) across the American states. The purpose of this dissertation is to explain this variance. Why are the various CPAs more successful in some states than others? The dissertation takes the form of three essays. In the theory essay (Chapter 1), I argue that different institutional characteristics of state legislatures make direct political strategies more effective in some state legislatures and indirect political strategies more effective in others. The empirical work in my dissertation takes advantage of two events at the federal level. The first is passage of the Affordable Care Act in 2010, which replaced DSH payments, a significant source of hospital revenue from the federal government, with a mandate that states adopt an expanded Medicaid (federal government insurance) program. The second is the subsequent U.S. Supreme Court ruling making this expansion optional. These events provide a unique opportunity to observe the political activities of hospitals across the country on the single (held-constant) policy issue of Medicaid expansion. In the first empirical essay (Chapter 2), I demonstrate the counterintuitive relationship between hospitals’ campaign contributions and a delay in Medicaid expansion. In the second empirical essay (Chapter 3), I identify and examine the effectiveness of two types of coalitions: vertical, comprised of the focal firm’s supply chain, and horizontal, which include ideological interest groups, local governments, and individuals not affiliated with the focal firm’s industry. Using data from state legislative committee hearing testimonies by hospitals and their coalitions on Medicaid expansion following the Affordable Care Act, I show a clear relationship between horizontal coalitions and the progress of Medicaid expansion bills. This effect is stronger in citizen legislatures.