She also wisely admitted that endorsements have very limited impact a lot of times. Ironically, due to her unique status and the nature of this race - an endorsement from her at the right time might actually have big time impact.
(for example, an endorsement of RS now might give him much needed legitimacy, or an endorsement of Newt could give him more tea party conservative cred, etc. Not saying she would do either, just thinking out loud about how she might make a difference ironically.)