The new health insurance marketplaces appear to be making little headway in signing up Americans who lack insurance, the Affordable Care Act's central goal, according to a pair of new surveys. Only one in 10 uninsured people who qualify for private plans through the new marketplaces enrolled as of last month, one of the surveys shows. The other found that about half of uninsured adults have looked for information on the online exchanges or planned to look. The snapshots from the surveys released Thursday provide preliminary answers to what has been one of the biggest mysteries since HealthCare.gov and separate state marketplaces opened last fall: Are they attracting their prime audience?