One implication of last week’s wins for Democrats in Virginia and Kentucky is that fewer people will perish because they lack access to health care.

To put it simply: “Medicaid coverage is literally a matter of life and death, particularly for people with serious health needs.” This is the conclusion of a new report from Matt Broaddus and Aviva Aron-Dine, colleagues of mine at the Center on Budget and Policy Priorities. Citing new, landmark research, the report estimates that between 2014 and 2017, the Affordable Care Act’s Medicaid expansion saved the lives of about 19,200 adults between 55 and 64. Another implication: An estimated 15,600 older adults in states that have refused to implement the ACA’s Medicaid expansion died prematurely.

In other words, partisan stubbornness is killing people.

Here’s the background. As part of the Affordable Care Act, Medicaid — the public insurance program that provides coverage to low-income households — was expanded to cover many more people. But a Supreme Court decision in 2012 meant that states could decide to turn down the federally financed program (the feds pay 100 percent of the costs of the expansion initially, which by 2020 phases down to 90 percent). Right now, the expansion is in place in 34 states and the District of Columbia.

Virginia and Kentucky took the expansion, but partisan forces in each state are actively trying to undermine the program. Though they’ve not yet been implemented, both states have adopted work requirements; Kentucky was the first in the nation to do so. This is a punitive policy that has been consistently found to result in lower coverage, not more employment.

Outgoing Kentucky Gov. Matt Bevin has waged a particularly vicious campaign against coverage for low-income Kentuckians: His own administration estimated that his Medicaid plan would have shrunk enrollment by 95,000, cuts that would probably have grown had he won another term. He promised to repeal the state’s entire Medicaid expansion covering more than 400,000 adults if the courts ultimately strike down his work requirement policy. (Bevin has yet to concede this race, though as of this writing, he lags behind his opponent, Democrat Andy Beshear, by more than 5,000 votes.)

When some places adopt a policy change and others do not, researchers have one of the more reliable ways to evaluate its impact. We then attempt to control for any other differences between the two areas; what’s left over probably has to do with the policy. A group of researchers did just that with the Medicaid expansion, comparing mortality rates between expansion and non-expansion states.

The figure below plots the difference in mortality rates between the two areas before and after the policy change. It shows that there were few systematic mortality-rate differences between expansion and non-expansion states before the ACA. After that, however, not only do such differences clearly appear, they increase over time. As older people achieve greater access to treatment, they’re better able to avoid death from diseases such as diabetes that are highly amenable to treatment (and potentially fatal if untreated).

Broaddus and Aron-Dine report that relative to those in non-expansion states, beneficiaries of the Medicaid expansions have been better able to fill their prescriptions for a variety of chronic conditions, and they’ve also received more preventive care, more mental health treatment and more cancer screenings leading to more early-stage diagnoses.

Lower mortality rates are not the only benefits of expanded Medicaid coverage. Similar research designs have found expanded coverage has reduced housing evictions, lowered medical debt levels and improved financial stability. Since the ACA has been in effect, the share of Americans without insurance has fallen sharply, contributing to an almost 40 percent drop in uncompensated care as a share of hospital budgets from 2013 to 2016 alone. For expansion states, that decline has been 55 percent, compared to just 18 percent in non-expansion states. Less uncompensated care means less medical debt, less pass-through of costs to others and stronger state budgets due to fewer losses at public hospitals.

This is good, empirical economics, but it ain’t rocket science. Despite conservatives’ relentless attack on Medicaid, it is a highly successful program, much valued by its recipients. I learned this early in life when I was a social worker in East Harlem, where families, especially those with kids, viewed Medicaid as not just health coverage, but as a source of financial security upon which they could build. Access to steady coverage — which, for the record, is the same for Medicaid as private coverage — is a huge stress reliever and a living-standards game changer.

Getting back to the politics, Democrats are deeply engaged in a national debate about major, structural changes to our health-care system. Given the prominence of the issue on voters’ kitchen tables, that make a lot of sense. Recent elections, including last week’s, also reveal that people trust Democrats more than Republicans to maintain and improve access. But as we argue about single payer, public options and other big ideas, let’s not lose sight of unfinished work right under our noses.

Expanding Medicaid to states where ideologically motivated governors and legislators continue to resist it, while strengthening and protecting existing programs, is a project that exists at that rare intersection of good policy and good politics. But this new research reminds us that it’s a lot more than that. It’s also a lifesaver.