In THIS universe Palin's negatives are too high. Spare me the "Ronald Reagan's negatives were high too" line. Palin is no Reagan. Spare me the "polls are lies created by the left" line also. If your neighbor or your brother in law or some people in your church supports Sarah Palin that's all well and good and means nothing on a national level.
In the 2008 elections there were people in my town, and the rest of the country working their ass off for Ron Paul but he still couldn't pull over 10% in any primary state. In the 2004 election there were Democrats screaming in their enthusiasm for Howard Dean but he still couldn't get the nomination. Just because a politicians supporters can make a lot of noise does not mean that that politician is adored across the board.
If Palin somehow pulls out the nomination her loss will be the most lopsided of any Republican since Kennedy/Goldwater. I seriously doubt she'll get the nomination though. Unfortunately my big concern is that the conservative vote will split too many ways in the primaries and Romney will cake walk to the nomination.
Now if you have evidence, other than online polls or straw polls (Ron Paul won lots of both of those) that Palin will win the nomination bring it on. I'd love to see it.
You make that challenge, knowing full well that NO prospective candidate has any better evidence of support, at this point.
In the final analysis, ONLY a primary will give us the answer we're looking for. Until then, what we have as tools to measure any prospective candidate's level of support, are online polls, Google hits, number of Facebook fans, book sales, number of public appearances (and attendance numbers), and the like.
Using those tools as a yardstick, Palin easily outdistances all other likely competitors.