The "Rodham" bit sounds good; it adds a bit of a hard-edged bite to all those L's (in Hillary and Clinton). It also allows her to keep an identity somewhat separate from her husband's (and lots of people still "don't like" Bill, to put it mildly). And it sounds much more elegant than a plain-vanilla John McCain.
I also wonder where the poll was conducted. If in NYC, then the different effect the addition of "Rodham" had on her chances vis McCain and Giulliani might be explained by the fact that a lot of New Yorkers still think of Giulliani as their hero (post 9/11). They also like her very well as their Senator (vide the polls), while their attitude to McCain is lukewarm at best.
Anywy.. Discussing pesidential potential more than ytwo years ahead of time seemss a bit silly. Let's think about it after Nov 8. Or whenever all the recounts and post election lawsuits tell us what's what in '06 (I'm not convinced that the DieVote machines won't slay us once again)