I think right now she's riding the money train of her popularity. No mystery to if she's running {IOW says no} then no more speaking engagements as people will quickly loose interest. If she is serious about running she needs to find better company. McCain can only hurt her chances any way you look at it.
She seems to be making good choices of candidates to support with her own donations so I say keep on making the dollars flow...all the better for the good guys she's supporting.
McCain won't hurt her chances at all for those who understand the politics of running...but she needs to limit this once the Ariz. deal is over.
She has enough good company at this point and likley will gain even more the closer it gets...again if she runs. Long way to go yet before all the players and endorsers step out.