This is a nice lesson—e.g., for an undergraduate class—in the process of “opinionation,” where a large fraction of the public suddenly acquires an opinion.
In the last week, Palin’s favorability rating has, well, paled. This demonstrates the consequences of a highly visible campaign: it is difficult for any Republican or Democrat candidate to command sustained attention without attracting roughly equal proportions of detractors and admirers. In a September 4 Rasmussen poll, Palin’s favorability was 1 point higher than McCain’s or Obama’s. Nine days later, according to a Sept. 13 poll by Daily Kos, it is slightly lower than theirs (49% vs. 55%; however, given the margin of error, it isn’t conclusively lower).
Of course, we would expect the usual polarization along partisan lines here, with most Democratic respondents having an unfavorable opinion and most Republican respondents having a favorable opinion.