The rising level of apparent cluelessness about how insurance and Obamacare works among the uninsured underscores existing concerns among ACA advocates, who have warned that signing up remaining uninsured people will be harder in the second season of Obamacare than in the first.
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The TCHS survey found that nearly 1 in every 5 people—or 19 percent—said, "I did not know how to apply" when asked in November why they didn't obtain Obamacare health coverage last year.
That's more than double the 9 percent who gave that answer when the question was asked in July 2014, three months after the close of the first open enrollment in Obamacare plans.
Ten percent of the respondents who failed to get health insurance last year said in November that it was because "I was not sure the insurance mandate applied to me," according to the survey. That's up from 7 percent who gave that answer last July.
In fact, the insurance mandate applies to nearly all Americans, although some exemptions are available.
The online survey, which was conducted for TCHS by Harris Poll, questioned 1,203 people in November, and was a "pulse check" for an earlier survey in July, which questioned 2,624 people.
TCHS, which conducts analysis and research on national health-care issues, is a division of the nonprofit Transamerica Institute, whose website says it is dedicated to identifying, researching and educating the public about retirement, health coverage and other relevant financial issues facing Americans.