Poll: Young adults least familiar with ObamaCare

Getting young adults to enroll is critical to the healthcare law's success. The administration is hoping that roughly 40 percent of the people who enroll in new coverage options next year will be younger than 35. If too few young people enroll, premiums for everyone else could skyrocket.

Overall, combining all age groups, a majority — 55 percent — said they're "somewhat" familiar with the law. Fifteen percent professed to being "very" familiar, while 30 percent were unfamiliar with it.

"Admittedly, the administration and like-minded groups still have some time to educate the public about the law, but they have a lot of distance to cover in terms of ensuring that the country truly understands the changes coming to the healthcare system," Gallup said.

Gallup also found, however, that young adults are less pessimistic about the healthcare law than older generations. Forty percent of young adults said they disapprove of the Affordable Care Act, compared with 54 percent of middle-aged respondents and 51 percent of those older than 55.

Approval rates were about the same, but young people were more likely not to have an opinion (perhaps because they're also less likely to be familiar with the law). Sixteen percent of young adults said they do not have an opinion about the law, almost three times higher than middle-aged respondents.

Overall public opinion of the law remains divided and somewhat negative, according to Gallup. Forty-nine percent of all respondents said they disapprove of the law, compared with 41 percent who approve and 11 percent who don't have an opinion.

Other public opinion polls have found basically the same division, and public attitudes have not changed much in the three years since ObamaCare became law.