Gallup and Rasmussen have the first overnight polling on Sonia Sotomayor's nomination to the U.S. Supreme Court. Although the two polls show a broadly similar, and moderately favorable, reaction, I'm going to focus on the Gallup data because it provides for a comparison with George W. Bush's three nominees to the Court.
Gallup asked its respondents to rate each nominee as excellent, good, fair or poor. I'm going to create a quick Likert-type score for each one, assigning 10 points for each response of 'excellent, 7 points for 'good', 3 points for 'fair' and 0 points for 'poor'; cases in which the respondent had no opinion on the nominee are discarded.
By this very rudimentary analysis, Sotomayor rates as a slightly more popular selection than Samuel Alito and Harriet Miers, and slightly less popular than John Roberts.
Still, the differences are small across -- just barely on the fringes of statistical significance -- the board. In certain ways, it's disappointing to see that the public wasn't better able to distinguish Roberts, who objectively speaking was a strong nominee, from Miers, who, um, wasn't. It seems like 80 percent of the public is making a snap judgment on the basis of partisanship (which should, of course, be helping Sotomayor because of the Democratic plurality right now) whereas only a small fraction are actually looking at the nominee's credentials.
Of course, public opinion can change as they learn more about a nominee -- as it did in an unfavorable way for Miers. So perhaps that small vanguard of people who are not judging the nominee on a partisan basis are leading indicators of sorts. Of the 18 Republican Senators who voted on Sotomayor in 1998, 7 or 39 percent voted to confirm her. Translated over the entire, 40-member Republican caucus, that would translate to 15-16 yea votes, which when coupled with what will presumably be 59 Democratic yeas, would produce a 74- or 75-vote margin for her overall. That would put her ahead of Samuel Alito's 58-vote confirmation (indeed, she could beat Alito without any Republican votes) but just behind Roberts' 78.