Most of the time, attempts to discredit political candidates by association are fallacious. Obama's candidacy is a case in point. His past contacts with William Ayers do not mean he is sympathetic to violent revolutionary politics; that case would have to be made on the basis of Obama's own words and actions. Ayers' attitudes don't transfer automatically to those he interacts with.
That's why this sort of thing would normally be irrelevant.
Minutes ago I spoke with friend Dr. Norman G. Marvin, M.D. and he is so concerned at what he has learned about Barack Obama’s family in Kenya that he is calling a special prayer meeting in his home to pray against the witchcraft curses attempted by them against John McCain and Sarah Palin.So some religious nutters in the USA are supporting the Republican ticket? So what? Unity's attempts to extend this sort of insanity to the right generally is fallacious in itself, a similar type of guilt by association but also a failure to distinguish between supersets and subsets - (all oranges are fruit::all fruits are oranges) -- (all loony religious types are Republicans::all Republicans are loony religious types). Of course, loony religious types infest all parties, even though the details of their lunacies vary.
The difference here, though, is that Palin herself has a history of direct involvement with exactly the type of fanatics on display in this episode. She has attended services held by a Kenyan witch hunter, one at least indirectly responsible for the death of a woman accused of witchcraft.
Palin should not suffer from guilt by association, no more than should any other politician. But her involvement with fringe religious extremism is direct, and should be held against her.