Right from the time she was announced as McCain's running mate, the mainstream liberal media feared Palin as another Ronald Reagan "game-changer" figure so they embarked on a campaign to "Dan Quayle" her.
They have succeeded in driving her negatives up by portraying her as a "not ready for prime time" floozy. Those SNL skits by Tina Fey were devastating. The majority of Americans continue to quote from that skit as though Palin herself said those words.
The second reason is that many Republicans do not like her either. When Palin was governor in Alaska, she went after corruption whether it was Democrats or Republicans. She is thus not a "team" player in their eyes. She is not one of the "good old boys club" in Republican circles.
That all said, I agree with you that her negatives are only an inch deep. Once she gets into the race and runs her campaign on her own terms, many Americans will see her for what she is - a citizen just like most of us who truly wants to advance the conservative cause and not just hold public office so that she can enrich herself through cronyism and power broking.
Now her negatives will always be high because she is a true conservative. Ronald Reagan always had hatred directed towards him by liberals because he was a real conservative who actually believed in what he said and acted accordingly.
How in the hell did Tina Fey have influence over the electorate. Thats one challenge than Palin does have is pop culture,
but my lord, people are having a hard time putting food on their table now. this will be a different election. a 1932 or a 1980