I posted this as a comment and thought others might be interested.   If you look at the history of the more recent polls, it would appear things are holding steady:

SurveyUSA:
On 4/8: Clinton 56 and Obama 38
On 4/1: Clinton 53 and Obama 41
On 3/11: Clinton 55 and Obama 36

Quinnipiac:
On 4/2: Clinton 50 and Obama 41
On 3/18: Clinton 53 and Obama 41

Rasmussen:
On 4/8: Clinton 48 and Obama 43
On 4/1: Clinton 47 and Obama 42
On 3/13: Cinton 51 and Obama 38

Whether it's a more favorable poll or a less favorable poll, things don't seem to be moving quickly in any one direction. Those of us able to volunteer need to keep our heads to the grindstone...there are still two weeks to go!