What matters is not what the polls say: what matters is WHO VOTES. It's a true "Tortoise-and-the-Hare" situation.
The key factors are that the Democrats' activist core is enervated, disillusioned, disappointed and dissipated. THEY'LL STAY HOME WARMING THEIR FANNIES IN FRONT OF THEIR SOLAR PANELS.
The Republicans are energized. THEY'LL SHOW UP IN SNOWMOBILES.
A quote from Rasmussen Reports....
Special elections are typically decided by who shows up to vote and it is clear from the data that Browns supporters are more enthusiastic. In fact, among those who are absolutely certain they will vote, Brown pulls to within two points of Coakley. That suggests a very low turnout will help the Republican and a higher turnout is better for the Democrat.