In general, I would agree with you. Take Perry, for example. Prior to him getting in the race, not many people knew who he was, and so his numbers as a presidential candidate were pretty low. Once he announced, people took a look, liked what they saw, and he jumped into the lead.
It is more significant with Sarah for a couple of reasons. First, while no one outside of Texas knew much about Perry, Sarah has had almost 100% name identification ever since 2008. She has been on national TV, had a reality TV show, been headlining Tea Party events - basically, she has been camapaigning for president almost non-stop since 2008. Most people have an opinion about her already, and despite her high public profile and constant media exposure, her negatives have stayed high, and her positives have stayed low. I don't see how her jumping into the presidential race will change her approval ratings. It will change the poll numbers for the primaries, as some of the Tea Party supporters will switch their support to her, but she will have a long, hard road to change the minds of people who have already decided they don't like her - and that appears to be close to 3/5 of the population. What are the people who don't like her going to see the day after she announces that they didn't see before to make them change their minds?
When someone is just an add-in the negatives will be high due to poll design, an element of which is tricking it up so that YOUR GUY (or customer) doesn't get the negatives.
Once she's a candidate the poll designs will change and the results will be different ~ and she'll have to pay for some of the work herself
If she runs.
If she doesn't run she'll have the same negative numbers 8 years from now if it comes to that.
But that image is media/RINO establishment created. Same as when she was in Alaska. She turned that around. She can do the same here with the same strategy...go directly to the people.
Cindie