Rossi's only hope is really to rekindle the public's dissatisfaction with the results of the 2004 gubernatorial election enough to make them give him the job he thinks he should have had. Given the trend of Gregoire's approval ratings, that does not seem very likely.
Agreed, at the beggining of Gregoire's term people were still extremely bitter about the results, but as time has gone by Gregoire's numbers have gone up quite a good amount, I would even venture to say that she is "popular", especially because she hasnt tracked too far to the left. Rossi most likely wont be able to get what he did last time, especially because all he has to run on is the "I should have won" slogan, but then again you never know...