Over the years, Sanders has tucked away funding for health centers in appropriation bills signed by George W. Bush, into Barack Obama’s stimulus program, and through the earmarking process. But his biggest achievement came in 2010 through the Affordable Care Act. In a series of high-stakes legislative maneuvers, Sanders struck a deal to include $11 billion for health clinics in the law.

The result has made an indelible mark on American health care, extending the number of people served by clinics from 18 million before the ACA to an expected 28 million next year.

As one would expect, the program was largely met with plaudits from patients and public health experts, but it has also won praise from even the biggest Obamacare critics on Capitol Hill. In letters I obtained through multiple record requests, dozens of Republican lawmakers, including members of the House and Senate leadership, have privately praised the ACA clinic funding, calling health centers a vital provider in both rural and urban communities.

In rural North Carolina, ACA-backed health centers now provide dental and nutrition services, while in San Francisco, the clinics provide translation services and outreach for immigrant families. In other areas, they provide mental health counseling, low-cost prescription drugs, and serve as the primary care doctors for entire counties. They have also served as a platform for innovation, introducing electronic medical record systems and paving the way with new methods for tracking those most susceptible for heart disease and diabetes.

Daniel Hawkins, vice president of the National Association of Community Health Centers, recalls that in the end Sanders was able to negotiate with Rep. Jim Clyburn, D-S.C., to increase health clinic funding through a special technical amendment that could modify the reconciliation Senate bill through a simple majority vote. The technical amendment passed, with $9.5 billion targeted for health center operations and $1.5 billion for construction and renovation projects. The House passed the final Senate bill, and President Obama signed the legislation with $11 billion in health clinic funding into law on March 23, 2010.

“There was no one who played a more important role than Senator Sanders,” Hawkins says, remembering Sanders’s constant lobbying of other lawmakers to support the funding.