Polls have been showing that the Iraq issue is fading compared to economic concern. Clinton's campaign clearly seems to feel that the risk of shifting positions to a much more strident anti-war position (all troops out in a year, except Embassy guards, etc.) by attacking Bush. Given the clever stirring of the spat prior to this debate (over the racial questions), Obama had to tone down his attacks, so that he could not accuse her of flip flopping.

This move neutralized the issue that works best for Obama (especially motivating young energy). The rhetorical ground then shifted to the question of who is best prepared to deal with the economy. That plays to Hillary's stimulus package, allowing her to give something to everyone and focus heavily on the sub-prime market to show the evils of special interests, etc.

So, her goal is clearly to focus on her (read Bill Clinton's) experience with the economy in the 1990's.

This debate seems to lead to the same kind of campaign that Bill ran in 1992. Don't like recessions, vote for a Clinton.

Argumentatively, Obama needs an answer to that. His answer is that he has a better chance to get some fix in place than Hillary does with a massive stimulus/spending package. But, that's a hard case to make, and he is not all that centered on it here. In short, Hillary wins if it's the economy, and Barack needs to make it the possibility of success.