People get checks from Social Security every month. People get their health insurance from Medicare. So when those programs come under attack, they immediately understand what it means and rally to their defense. But while the ACA (OK, OK, Obamacare) has wide-ranging implications and effects, it won't be a program in the same sense. Though many millions of people will have insurance because of Obamacare, no one will get their insurance through Obamacare. They'll get private insurance, or Medicaid.
(Screenshot above from a new Obama campaign Facebook page)