Patrick is one of those politicians where a favorable/unfavorable rating is not very useful, since most people kind of think he's a good guy, and where approval is dependent on what you ask.
The Rasmussen questions are actually more informative by dividing things into Excellent, Good, Fair, Poor. This is important because most people in the state would not rate him as poor, but most also don't think he is doing a good job.
Anyway here are the October Rasmussen results:
How do you rate the way that Deval Patrick is performing his role as Governor? Excellent, good, fair, or poor?
6% Excellent
32% Good
39% Fair
20% Poor
3% Not Sure
http://www.politickerma.com/jeremyjacobs/1553/rasmussen-patrick-s-job-approval-dips-38-percentBasically Patrick has very weak dedicated support, about a third of the population that likes him somewhat, and a fifth who hate him. The remaining 40% are unhappy with his performance, but are currently gravitating between keeping him or not.
In a good year for the incumbent's party, this is not a fatal situation. Most responders who say "fair" will come home. But with an unpopular legislature, a billion dollar local aid cut coming up, and the potential of 2010 being an anti-incumbent midterm, those numbers could turn south for Patrick really quickly.
That said, I would not put him in the very vulnerable category so much as the potentially vulnerable. Depending on events he will either lose 51-47 or win 53-44.
