Wretchard @ 6 beat me to it.

I have long ceased to be surprised at how persons can deceive themselves; and at times, as Joseph Goebbels understood, the bigger the lie the more convincing it can be, even to the person deceiving himself or herself. At this point the person can seem sincere and be quite convincing.

Many studies about cognitive dissonance show that when behavior and beliefs are in conflict and the behavior continues, the beliefs will gradually become congruous with the behavior in order to remove that internal conflict. I have no idea what Nancy Pelosi believes at present, but I think that as time goes on she will more and more believe what she claims to be true. And in the process she will convince some others.

Jim