No. The fact is that the greatest "issue" difference between Rudy and Hillary/Obama lies in support for the WOT. The typical "centrist Dem" is going to side with the mainstream Dems on this, so no soup for Rudy. Meanwhile that very agreement between Rudy and the Dems on the social agenda will sink him with SoCons.
What "centrist Dem" group do you anticipate Rudy will pull? Hard core Union? Farm subsidy dems? Southern traditional yankee haters? American Idol watchers?
If it weren't for the front loaded primaries occurring in Feb, the traditional grass roots approach of vetting nominees would probably still be valid.
Which is why the fight's getting bloody now, 10 months out from that. Frankly, I think it's going to depend much more on who the Dems are likely to nominate. If, 8 months hence, Hillary has imploded, Obama has gotten spanked for inexperience, and the Dems are pushing a current Dark Horse like Richardson, then the Fear Factor support for Rudy will tank.
This is the crux of the issue; your assertion can be judged as being directly contradicted by Lieberman's victory in CT. There is a big difference in protesting against the war in order to score political points vs really wanting the US to lose.
The Rudy calculus is simple: are there more than enough centrist Dems who, even though they oppose the war, would really vote for defeat vs the number of SoCons who will not vote for a social liberal?
I think it's going to depend much more on who the Dems are likely to nominate.
Rudy matches up well against Hillary! due to the fear factor which might induce some SoCons to still vote for Rudy. However, I do not believe Gore engenders the same level of visceral dislike, which might be a problem in a tight race. Under that scenario, I think Gore takes in 2008 if he is nominated by the Dems.