They're a key piece of Obama's law, but if not enough young, healthy Americans enroll in the marketplace, costs will be higher for everyone who participates. Republicans and their allies -- hopeful that higher rates will convince more people the law should go -- have been working to dissuade Americans from signing on, including in a pair of Web videos last week that featured a demonic Uncle Sam performing medical exams.
"Don't let the government play doctor. Opt out of Obamacare," conclude the ads, which were backed by a libertarian group funded by the conservative Koch Brothers.
Obama will begin another push to explain the law amid his efforts at global diplomacy in New York, sitting down with his Democratic predecessor, former President Bill Clinton, in a public discussion of the law on Tuesday evening. Clinton previously delivered remarks defending the law at his presidential library in August.
Coming a week ahead of the exchanges' official opening date, a White House official describes the event as "part of a ramped up public education effort to reach Americans who want to sign up for new affordable options in the health insurance Marketplace."
That effort -- which continues Thursday when Obama touts his law in Maryland -- comes as polls show Americans, particularly those who Obama is trying to reach, don't understand the law. In a Wall Street Journal poll earlier this month, 76% of uninsured respondents said they didn't understand the Affordable Care Act or how it might affect them.