healthcare.gov vulnerability?

It occurred to me that I haven't heard much on the news about deliberate attacks on the healthcare.gov website, even though it is reputed to be extremely weak.  Might somebody (potentially a supporter of Obama and/or Obamacare) have deliberately 'spammed' it with fake signups, simply to get the number of such signups increased?  How vulnerable would it be to 'invented' names/addresses?  How 'valid' would these names/addresses have to be to keep the system from finding out until some arbitrary stage in the process?  If such an attack had been done, would the public ever find out, and when?         Jim Bell