In the latest rasmussen reports poll released today, the results of the top 3 were:
Clinton 34 (35)
Obama   26 (26)
Edwards 15 (14)

(trendlines are from the previous week)
Let me first start by saying that the poll title is pure snark.  Hence the "quotes".  While Hillary has dropped 1 point and Edwards has gone up a point, in reality, there has been no movement.  1 point in either direction is not relevant.  What this does show is a very stable national race.

As Rasmussen points out

Among Presidential hopefuls, this is the fifth straight week that Clinton has been at 34% or 35%. She has been within three points of the 35% level in fourteen of the last 15 weekly updates.

Stability is found throughout the numbers for all candidates. This week is the fourth time in five weeks that Obama has been at 25% or 26%. While the newcomer to national politics enjoyed a brief expansion of support heading into the first debate among Democratic hopefuls, he has generally been in the mid-20s. Obama continues to do better than Clinton among independents likely to vote in a Democratic primary.

Edwards has consistently been in the mid-teens (eleven straight weeks within three percentage points of the 15% mark). Other polls and anecdotal evidence suggest that Edwards is leading in the first caucus state, Iowa. Obama is from neighboring Illinois and might also do well in Iowa. If Clinton continues to hold solid leads in the national polls but does poorly in Iowa, it is likely to dramatically shake up the race.

I think the stability that this shows is relevant for gaging whether or not the debate last night had any impact.  All of this polling was done pre-debate.  All of next weeks numbers will have been conducted post-debate.  If next weeks numbers show any statistically significant movement it will likely be because of the debate and, of course, the post-debate spin.

UPDATE: I added a poll option to indicate no change.