My second chart here shows what actual enrollment would look like, depending on how many plans are ultimately selected and how bad the attrition rate is over the first few months of operations. As you can see, it ends up below the CBO’s projection in most cases, sometimes far below. But if signups accelerate significantly, and attrition is minimal, the exchanges may hit the CBO number. Especially when you take into account the de facto extension of open enrollment at least into April.

Does that mean that Obamacare will basically be beyond repeal, as its supporters hope? It certainly makes things harder. But we still don’t know how many of these people are newly insured, or how many of the previously insured like these policies better than their old policies — nor how much pressure it is going to end up putting on the budget. Those are things we won’t know for quite a while. But if it were impossible to ever cut off an expensive entitlement that goes to the middle class, TennCare would never have been cut.