If moveon.org were serious about trying to advance clean air legislation, and if it were serious about keeping Democratic dominance over the Republican party, it would not be running this ad.
What, is Sarah Palin going to change her mind about the Clean Air Act because moveon.org put a negative advertisement about her on the internet? For Palin, being criticized by moveon.org is something good — it’s evidence that she still matters.
The better move for moveon.org would have been to use the same ad to put pressure on Republican members of Congress from closely-divided states or districts, who are opposing the laws they are trying to advance. They would not use Sarah Palin as the personification of the Republican Party; they underestimate the degree and manner which their political opponents will reflexively and unthinkingly react to criticism of St. Sarah of Wasilla.
What they should do is treat Palin as what she is — politically irrelevant — and focus their energies on people who are vulnerable to the kind of pressure that moveon.org can bring, not to spend those energies on people who will profit from their attacks.