NO.
And, NO.
That's just my opinion. I'm not going to attempt to divine Sarah's motivations for backing McCain in this race, and I'm not going to condemn her for it, either. I respect her far too much to do that.
Having said that, I would prefer that she not sully herself by any further association with him. I would have advised her to support him privately (if she had to), but to stay far away from publicly supporting his Senate race.
The conservative base rightly despises this man, and everything he's done to undermine the conservative agenda in the last decade. Sarah ought to know that most of us voted for her in 2008, not Juan McCain.
She should follow Rush's example and stay out of the Republican primary fights alltogether. If McStain wins the primary, then campaign for him in the general.