This whole "he should be winning by XX points" argument always gets me.  In 2004, Bush got 51% of the vote.  I almost believe that, if it was possible for him to run for a third term, he would at least be hovering in the low 40's right now, and I would probably give him 45% odds of ultimately winning reelection.  And, people like McCain better than Bush.  

The days of large-scale, Reaganesque blowouts are over.  I don't even think it's possible to approach Bill Clinton's victory over Dole in today's environment.  Fox News and talk radio keep slightly less than half of voters loyal to the Republican brand, even if they don't like the particular candidate that the Republicans field.  And, because McCain isn't Bush, Republicans dissatisfied with Bush can at least hope that McCain would be different.  

I know it's fun to throw out imaginary numbers to show how well the nominee would be doing if he followed your advice, but if so perhaps you could put forward a plausible scenario in which all of these hypothetical votes would materialize.