There’s growing optimism among Obamacare advocates that the Affordable Care Act could reach seven million sign-ups by the end of March. The administration at first embraced the number — which originally came from the Congressional Budget Office — only to back away from it when the problems of the federal Obamacare website became apparent. Now, with word that 2.1 million have so far signed up for private insurance, some of that pre-rollout confidence is coming back.

It’s well known that in its effort to reach seven million, the administration redefined “enrollment” to mean anyone who has chosen a health plan — not just those who have actually purchased one. So there are serious questions about the 2.1 million figure. But perhaps the bigger question about the Obamacare number is: How many of the people who are now purchasing coverage on the exchanges are doing so because they lost the coverage they already had because it did not meet Obamacare standards?