Access to health care is both a cause and consequence of inequality in the United States. To address lack of access to care for the poor, the federal government initiated the Community Health Center (CHC) program in 1965 as part of the War on Poverty. The CHC program—unusual for its bipartisan support and mission to defy socioeconomic stratification by serving anyone regardless of ability to pay—provided care for nearly 30 million predominantly poor patients across 13,000 clinics in 2019. Given its substantial growth in recent years and direct contact with millions of socially and economically marginalized Americans, the CHC program is an important institution for understanding how structural conditions impact population health and inequality. This dissertation uses three complementary methodological approaches to examine the political, social, and spatial dynamics of the CHC program. The first empirical chapter draws upon nearly forty years of historical evidence and leverages a comparison with Medicaid—a highly-contentious policy sharing the same purpose, place, and period—to understand how CHCs avoided controversy. I argue that policymakers’ initial articulation of frames aligning with both morals and markets allowed the CHC program to resonate across ideological divides, while Medicaid’s lack of market alignment and pervasive framing as inequitable inhibited its political support. The next chapter relies upon a qualitative case study of a small-town health center to explore the interpersonal, organizational, and institutional mechanisms underlying how CHCs deliver care to low-income patients. Describing how shifts toward marketization have impacted the safety net setting, the findings extend scholarship on stigma and poverty governance at the nexus of debates over health care as a right versus a commodity. The final empirical chapter uses a novel historical dataset to document geographic variation in Hispanic immigrants’ proximity to CHCs since 1970, highlighting how access to CHCs may be a crucial yet underexplored factor in understanding the health of this disproportionately uninsured population. In the conclusion, I discuss the theoretical, substantive, and policy implications of the findings, as well as opportunities for future research addressing the longstanding disparities in access to health care for low-income Americans.