One in 10 veterans lacks health insurance. Obamacare could change that.

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The Veterans Administration operates the country's largest health-care system. It has more than 1,700 hospitals and clinics across the country. Doctors there had about 50 million appointments with veterans in 2012. This sweeping system does not, however, cover everyone: One in 10 veterans lacks health insurance.

That statistic comes from Jennifer Haley and Genevieve Kenney, two researchers at the Urban Institute, who have spent a good part of the past year looking at the uninsured rate among veterans -- and how the Affordable Care Act might change it.

'When we look at pre-Affordable Care Act, in terms of Medicaid, we're finding about one in 10 uninsured vets looks like they might qualify for Medicaid,' says Kenney, a principal research associate at the Urban Institute. That will increase significantly under the health-care law, although not in states that are declining the Medicaid expansion.

Veterans are not automatically eligible for Veterans Health Administration benefits. Instead, enrollment depends on meeting certain requirements, for instance, serving 24 continuous months. Priority and access to doctors depends further on other characteristics like service-related disabilities and income. But veterans do tend to have a lower uninsured rate than other Americans -- 10 percent rather than 18 percent -- largely because of their access to the VA.

Some veterans may be eligible for VA benefits but not enroll, although Kenney says there isn't especially robust research on this point. Some might not be aware that they're eligible or, if they know, see the sign-up process as too complex to navigate.

'While the VA system is large, it doesn't reach everywhere, which could be a complicating factor if you don't live in close proximity to a facility,' she says.

In a research brief published in May 2012, Haley and Kenney have estimated that about 1.3 million veterans currently lack health insurance coverage. That works out to a little over 10 percent of the 12.5 million veterans in the country. An additional 0.9 million adults and children in veterans' families also lack insurance coverage.

Uninsured veterans differ from insured veterans, in that the former have lower levels of education and younger average ages.

'Uninsured veterans are less likely than insured veterans to report service-related disabilities, perhaps reflecting greater eligibility for and use of VA care among those with service connected injuries and illnesses,' Haley and Kenney write. 'Uninsured veterans are also younger than insured veterans, on average.'

Uninsured veterans report a lower level of education -- 47.3 percent have no high school diploma, compared to 30.7 percent of insured veterans -- and higher levels of unemployment (23.4 percent vs. 5.7 percent). Their lower likelihood of being employed is likely a partial explanation of why they lack health insurance coverage.

Haley and Kenney wrote a follow-up paper in March 2013, looking at what the Affordable Care Act would mean for uninsured veterans. They estimate that about 40 percent of uninsured veterans earn less than 138 percent of the federal poverty line (about $15,000 for an individual) and would therefore qualify for Medicaid, if their state had opted to expand the program.

But, as we here at Wonkblog know, not all states are expanding Medicaid: 24 have opted not to move forward with the expansion. Kaiser Family Foundation tracks these states in orange below (one small caveat: Pennsylvania has agreed, in principle, to expand Medicaid but still needs the federal government to okay its rather unique plan to do so.)Haley and Kenney came up with an estimate, back in March 2013, for how many veterans could be left out of the Medicaid expansion. The researchers estimated that 250,000 veterans potentially eligible for Medicaid lived in a state committed to expanding. Another 144,000 veterans, who were below the poverty line, would be left out, as they lived in non-expansion states.

The numbers have shifted a little bit as some states have made up their minds -- or changed their decisions -- about Medicaid expansion plans.

'You're much more likely to see a reduction in the uninsured among low-income veterans in the states that are expanding,' Kenney says. 'You have to think about their families, too, who could also be part of a gap that is closing.'

Kenney also thinks there could be a bit of an increase in VA coverage, too, with the national conversation around a health insurance expansion that could get some veterans looking anew at their options.

'The VA could become aware of the uninsured and connect them with their options for coverage,' she says. 'This is obviously new terrain, but you could imagine a new, national discussion could increase awareness of different sources of coverage.'

KLIFF NOTES: Top health policy reads from around the Web.

The White House is leaning heavily on insurers to help with enrollment. 'The White House is increasing its reliance on insurers by accepting their technical help in efforts to repair the problem-ridden online health insurance marketplace and prioritizing consumers' ability to buy plans directly from the carriers. The Obama administration's broader cooperation with insurers isa tacit acknowledgment that the federal insurance exchange - fraught with software and hardware flaws that have frustrated many Americans trying to buy coverage - might not be working smoothly by the target date of Nov. 30, according to several health experts familiar with the administration's thinking.' Juliet Eilperin and Amy Goldstein in The Washington Post.

State exchanges aren't talking much about the individual mandate penalty. 'While the mandate for all Americans to buy health insurance - with a penalty if they do not - was the linchpin of the Supreme Court decision upholding the law, and is considered the key to its success, poll after poll has found that it is also the least popular part of the program. State exchange operators say that they are not trying to hide the penalty, but that their market research has taught them that, at least in the initial phase, consumers will be more receptive to soothing messages and appeals to their sense of collective responsibility than to threats of punishment.' Aneoma Hartocollis in The New York Times.

It's going to be difficult for the White House to 'fix' insurance cancellations. 'Policy wonks on both sides of the health care debate held open the possibility that the administration will come up with something - there have been too many surprises already in the implementation process to rule anything out. But it's hard to see what the White House could do, on its own and specifically without Congress, that would make much of a difference.' Sam Baker in National Journal.