With the U.S. Senate moving quickly towards a vote on the repeal and replacement of the Affordable Care Act, politicians are facing questions about how the legislation would affect their constituents. Recent estimates from the nonpartisan Congressional Budget Office indicate that 22 million Americans would lose health insurance under the Senate’s Better Care Reconciliation Act. But what does this mean for Louisiana? According to official state statistics, expert projections, and our own survey of adults in the state, it means a great deal: health care for nearly half a million Louisianans is at stake.

In January 2016, Gov. John Bel Edwards signed an executive order expanding the state’s Medicaid program under the ACA, making most low-income adults eligible for the program for the first time. The majority of those eligible are in working families with jobs that do not provide affordable insurance

Official state statistics show that, in the expansion’s first year, nearly 430,000 newly eligible Louisianans enrolled in Medicaid and gained access to needed medical care. More than 96,000 have received preventive care, including 14,000 screened for breast cancer, 10,000 screened for colon cancer, and 2,500 diagnosed and treated for diabetes.

Meanwhile, in research conducted at the Harvard School of Public Health, we have studied how Medicaid expansion is affecting adults compared to those in other Southern states. In late 2016, we surveyed nearly 3000 low-income adults in Louisiana, Arkansas, Kentucky and Texas. Kentucky and Arkansas expanded coverage under the ACA in January 2014, while Texas has not expanded.

Our survey shows significant benefits from Louisiana’s Medicaid expansion. Between 2013 (before the ACA was implemented) and 2016, the uninsured rate among low-income adults in Louisiana dropped by more than half, from 42 percent to 15 percent. Meanwhile, in neighboring Texas, the change was much smaller — from 39 percent in 2013 to 28 percent in 2016. Louisianans are also more likely to report having a personal doctor and having had an office visit in the last year, compared to their counterparts in Texas.

Other research we have done shows that these interactions with the health care system through Medicaid expansion have major benefits over time, including chronic disease management and improved health status. Additionally, research has shown that Medicaid expansions may help people live longer by reducing the risk of death from conditions like diabetes, cancer, and heart disease.

Our survey also showed that positive attitudes toward the ACA were much higher in Louisiana, compared to Texas. Public opinion polls show similar national trends. As more Americans have experienced the benefits of the ACA and Medicaid expansion, the law’s approval ratings have improved.

Nonetheless, both the House and Senate have proposed bills to repeal and replace the ACA. Both bills would phase out the federal funding that makes Medicaid expansion possible in states like Louisiana. The bills would also make additional deep cuts to Medicaid over time, likely reducing Louisiana’s ability to provide Medicaid to children, disabled adults, and older people in nursing homes.

A key question in the debate is how Republican senators from Medicaid expansion states, such as Louisiana’s Bill Cassidy and John Kennedy, will vote. One recent analysis of the Senate bill concluded that it would result in a $2.68 billion decline in federal funding to the state by 2022 and 410,000 Louisianans losing health insurance coverage. In other words, the Senate bill would endanger access to health care for thousands of Louisiana’s working class families, leave many of the state’s hospitals in financial turmoil, and cost the state budget billions of dollars.

As evidence piles up from numerous studies on the benefits of health insurance, the nation as a whole and Louisiana in particular stand at a critical moment. Will members of Congress eliminate coverage for millions of Americans and for nearly half a million Louisianans, or will they instead pursue bipartisan and meaningful reforms to improve the ACA? Louisiana’s elected officials will play a critical role in that decision, and the time to make that decision is drawing near.

Carrie Fry is a doctoral student in health policy at Harvard University, and Benjamin Sommers is an Associate Professor of Health Policy and Economics at the Harvard T.H. Chan School of Public Health and a primary care physician at Brigham & Women’s Hospital in Boston.