The percentage of adults who lack health coverage plunged in the first quarter, reaching a record low just as the Supreme Court prepares to rule in a case that could reverse that Obamacare-fueled trend.
That rate—the lowest since the index began tracking health insurance status in 2008—is 1 percentage point less than the prior quarter.
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And it is 6.1 percentage points lower than the record high hit in the third quarter of 2013, right before Obamacare exchanges began selling private health plans and directing eligible people to government-run Medicaid programs. The Obamacare mandate requiring nearly all Americans to have some kind of health coverage or be subject to a tax penalty began in 2014.
Among ethnic groups, Hispanics and African-Americans saw the biggest declines in uninsured rates, with percentage point drops of 8.3 and 7.3 percent respectively since late 2013. But Hispanics remain, by far, the group least likely to have health coverage, with 30.4 percent of Hispanic adults uninsured as of early 2015.
Among age groups, adults ages 26 to 34 saw the largest decrease in their uninsured rate since late 2013, a 7.4 percentage point plunge. And among economic groups, people who earned less than $36,000 annually saw a much bigger drop in their uninsured rate compared to other groups. Since 2013, that rate fell by 8.7 percentage points to 22 percent last quarter.
In article summarizing the latest insured rate findings, Gallup.com noted that "an improving economy and a falling unemployment rate may also have accelerated the steep drop in the percentage of uninsured over the past year."
"However, the uninsured rate is significantly lower than it was in early 2008, before the depths of the economic recession, suggesting that the recent decline is due to more than just an improving economy," Gallup said.
The survey found that the percentage of people enrolled in health plans paid by themselves or a family member—as opposed to people in job-based health plans—grew from 17.6 percent in late 2013 to 21.1 percent in the first quarter of 2015.
Enrollment in Medicaid also grew, from 6.9 percent of adults in late 2013, to 9.0 percent last quarter.
Although private insurance plans sold through government-run Obamacare exchanges, which signed up about 11.7 million people this year, get the lion's share of media attention, Medicaid has played a major role in driving down the uninsured rate. That is particularly true in states that expanded eligibility for that program to include nearly all poor adults.
The 2012 decision upholding much of the Affordable Care Act also said the ACA could not compel states to expand Medicaid. The Montana legislature in recent days has moved toward making the state the 29th, along with the District of Columbia, to adopt Medicaid expansion.
In June, the Supreme Court is expected to rule on another Obamacare-related case, one that could send the uninsured rate up again.
In that case, plaintiffs claim that customers of HealthCare.gov, the federally run Obamacare exchange that serves 37 states, cannot receive tax credits that help them pay their monthly premiums. Almost 90 percent of HealthCare.gov customers get such financial assistance for their insurance.
The plaintiffs claim that only customers of a state-run exchange can receive those tax credits, because the ACA does not explicitly authorize them for enrollees of a federally run exchange. The ACA does explicitly state that customers of state-run exchanges can get the credits.
If the Supreme Court rules for the plaintiffs, experts estimate that 8 million or more people will lose their insurance, either because they will be unable or disinclined to buy it without the federal tax credits, or because premiums will rise so much in HealthCare.gov states as a result that some people without subsidies will be unable to afford it.