If you don't need Obamacare, you probably don't like it. But even if you need it, you still probably don't like it—or even care about it.
A survey of nearly 8,000 adults released Monday by the Urban Institute found that white, middle- to upper-income adults who already have private insurance and who are in good health are the most likely group to have an unfavorable view of the Affordable Care Act, commonly known as Obamacare.
Nearly 45 percent of insured people surveyed had unfavorable opinions of Obamacare, compared with just 27.5 percent with positive views. The rest said they have no opinion.
But as the Obama administration renews efforts to encourage enrollment in Obamacare health plans, the survey also shows weak support among the groups that are seen as being most likely to benefit from health-care reform.
The survey said uninsured people with lower and middle incomes expressed "only weak support" for the ACA, "and were more likely to have no opinion than to have a favorable view."
Nearly 38 percent of the uninsured questioned had "no opinion" of Obamacare, according to the survey released Monday by the Institute's Health Policy Center, the full results of which can be found here.
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Of the uninsured who had an opinion, 31.3 percent viewed the ACA unfavorably. Barely 29 percent of the uninsured had a favorable view, according to the survey, which was conducted just before the October launch of the Obamacare exchanges selling insurance plans.
Those results are striking because offering affordable health coverage to the uninsured is the main goal of Obamacare, whose open enrollment period for 2014 coverage ends March 31.
Another result that stood out was the perception of Obamacare among people who earn between 138 and 400 percent of the federal poverty line. That's the income band that qualifies someone to buy ACA insurance with government tax credits, which can significantly lower premium and out-of-pocket medical costs.
More than 43 percent of those respondents had a negative view of the ACA, while just 24 percent had a positive view. The rest had no opinion.
Even people who were affected by a Obamacare provision that predated the October launch of the ACA exchanges selling insurance were, more often than not, negative about the law. Those provisions include allowing adults under age 26 to remain on their parents' health plans.
More than 40 percent of people affected by an Obamacare provision by the fall of 2013 had a negative view of the law, versus 34 percent who had a positive views. The rest had no opinion.
"It is clear that support for the ACA is relatively weak among all the groups that we examined ... who stand to benefit directly from the provisions of the ACA that are being implemented," wrote the authors of the survey.
That "suggests that public education and outreach efforts are falling well short of reaching and informing the ACA target population who stand to benefit from the coverage provisions," they added.
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"Large percentages of those in fair or poor health, those with lower incomes, the uninsured, racial/ethnic minorities and the young have no opinions one way or the other about the law," the authors wrote. They noted that about 40 percent of both Hispanics and of nonwhite Hispanics had no opinion on the law.
"Understanding and addressing the lack of support" among those groups "will be essential to increasing ACA engagement and achieving the increases in coverage sought under the law," the authors wrote.
The results come as the White House announced Monday that President Barack Obama will participate in a town hall meeting Thursday, co-sponsored by several major Spanish-language media outlets and aimed at getting Latinos to enroll.
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Over the past weekend, the White House said, there were Latino and African-American "enrollment summits" held in a number of major U.S. cities.
The events are part of an enrollment push ahead of the March deadline.
—By CNBC's Dan Mangan. Follow him on Twitter @_DanMangan.