Hillary will only run if she thinks it will be easy. No tough questions, no accounting for her prior bad acts, etc.
When she ran for Senate the first time, Rudy was dealing with prostate cancer, and decided not to run. Who was her competition ? Rick Lazio....Not to slam him, and he did the best he could, but he ws just not a strong candidate.
This time, fist Jeanne Pirro is in then out then some other idiot. Again, no competition, and she was the incumbent.
Hillary has got to know that the daggers will be hout for her, namely that of Peter Paul who is seriously PO's with how they scammmed him. Her campaign finance directer pled guilty to some fundraising thing related to the Paul mess.
The there is Osama Obama, The hairdoo(Edwards), The War Hero(Kerry), and an assortment of other democRATS who are every bit as determined to keep the Clintons out of the WH.
I don't think she'll run in a hotly contested race. But if things get weird, and she thinks she has an easy shot at it...she will get in.