Eighteen percent of Americans, or fewer than one in five, say they or someone in their family is better off because of the Affordable Care Act, according to a new poll by CNN. Nearly twice that number, 35 percent, say they or someone in their family is worse off. A larger group, 46 percent, say they are about the same after Obamacare as before.

In nearly all demographic categories — age, income, education, etc. — more people say they are worse off because of Obamacare than say they are better off.

For example, one might expect respondents with incomes below $50,000 to be somewhat likely to say Obamacare has helped them. And that is the case: 21 percent say they are better off because of the Affordable Care Act. But 35 percent say they are worse off. (Forty-four percent are the same.)

Likewise, one might expect young respondents to report benefits from Obamacare. And they do: 23 percent say they're better off. But 33 percent say they're worse off. (Forty-three percent are the same.)

In other categories, the gap between better off and worse off is larger. In just one demographic group, nonwhites, is the group of those who say they are better off, 29 percent, bigger than the group who say they are worse off, 17 percent. (Fifty-four percent say they are the same.)

CNN also asked a slightly broader question, in which in addition to asking if the respondent or his family is better off, the question also asked if "other families in this country" are better off because of Obamacare. Thirty-five percent of respondents said that other families are better off, while 44 percent said Obamacare has "not helped any families." It's not clear if those answers were based on personal knowledge, news reporting, ideology, or some other factor, so for that reason, the information doesn't seem nearly as valuable as the straight question of whether the respondent or a family member is better off.

The CNN numbers are basically consistent with other surveys. The most recent Kaiser Family Foundation poll, for example, found that 18 percent said that they or their family were better off because of Obamacare, while 26 percent said they were worse off and 53 percent reported no difference.

Numbers like those in the CNN poll are always subject to partisan interpretation. For example, Obamacare supporters could add the 18 percent who are better off with the 46 percent who are the same and argue that 64 percent are better off or the same after Obamacare. The law's opponents could add the 35 percent who are worse off to the 46 who are the same and argue that 81 percent are worse off or the same. But the basic better off-worse off number is as solid an indicator as we have of how many people Obamacare is helping or hurting. And if the polling is correct, Obamacare is leaving more people worse off than better off.