The same poll gives 8 of 17 of Gore's percentage points to Clinton, 6 to Obama and 2 to Edwards.
http://www.pollingreport.com/wh08dem.htm
For a few reasons, I expected Obama to close the gap eventually but not this soon. Note that this particular poll has a small sample size (a little over 400) and a relatively large margin of error of +-5. The ABC poll a few days earlier still shows Clinton with a 12-point lead, although Obama has a net gain of 5 points since their last poll. The trend is moving in that direction overall.