I'm not sure that is really true, and I don't see the negative correlation with the stock market's movements that you assert. However, it is an observable fact that his rhetoric is no longer having the effect in mobilizing support that it had say two years ago.
I believe the difference is that, though his rhetoric is still focused on the political as-pects of campaigning for the next election and on mobilizing various elements of the electorate to support his political views, in the eyes of a very large number of Americans he should now be more focused on finding concrete, realizable solutions to the specific challenges before us instead of just playing the political blame game.
As a senator Obama voted against an increase in the debt ceiling for stated reasons nearly identical to those currently professed by the tea party. His current rhetoric directly contradicts his words then.