Who said she “let it get away”?
She needs to NOT say a word and let others do it. She is just as much a socialist and does not want to be associated with Ayers in any way.
This is *exactly* what Hillary has been frustrated about. She knew that Obama has some skeletons in his closet that are okay for Chicago politics, but that are total showstoppers for national office. But what could she do? Destroy the left wing legend with right wing arguements? It's one thing for her to see the bus heading towards Barack, but to push him towards it would be political suicide.
If you think about it, all of her actions for the last year make sense. She knows he'll be eviscerated by the Republicans, but if she eviscerates him first, she'll take the blame, and her dream of being President dies forever.
All she can do is what she's doing now. Look at the crowd look at her, everyone knowing that Barack is doomed, and that Hillary would have won, and let that thought soak in, so it's deep and ingrained by 2012. She can't steal the election now, but she can bargain for her position next time in electoral blood.