He was talking about the American voter, here is what he said:
Originally Posted by Conservative
This bill was written in a tortured way to make sure [the Congressional Budget Office] did not score the mandate as taxes. If CBO scored the mandate as taxes, the bill dies. OK? So it's written to do that. In terms of risk-rated subsidies, if you had a law which said healthy people are going to pay in — you made explicit that healthy people pay in and sick people get money — it would not have passed. OK? Lack of transparency is a huge political advantage. And basically, call it the stupidity of the American voter
or whatever, but basically that was really, really critical to get the thing to pass. Look, I wish ... we could make it all transparent, but I'd rather have this law than not.
Read more at snopes.com: Obamacare Architect Jonathan Gruber Hails American 'Stupidity'