Like Orin and Eugene, I'm an admirer of Judge McConnell. Among other things, he once offered a seminar at the University of Chicago on "Economic Liberties and the Constitution." I have no idea what his views are on such issues (I'm recalling, from seeing his syllabus many years ago, that the seminar discussed Lochner, commercial speech, takings, the constracts clause, and the dormant commerce clause, but my memory may be faulty), but I like the idea that a potential Supreme Court nominee thinks that constitutional protection of economic liberties is important enough to warrant teaching a class on the subject.
However, I think that if McConnell were to be nominated, his opponents would have such a good (albeit unfair) soundbite against him that I'm not sure that he could survive it. He wrote, in discussing the 1954 case of Bolling v. Sharpe, that "[t]he suggestion that the Due Process Clause of the Fifth Amendment prohibits segregation of public facilities is without foundation." Balkin, ed., What Brown v. Board of Education Should Have Said, p. 166. The view that the Fifth Amendment does not prohibit discrimination by the Federal Government is a perfectly respectable originalist viewpoint, though, as I discuss in a recent Georgetown Law Journal article, I believe that originalists have vastly exaggerated the perceived problems with Bolling specifically, and more generally with the idea that the Fifth Amendment's Due Process Clause includes an antidiscrimination principle (indeed, I believe that Bolling was arguably more justified in terms of text and history than its companion case, Brown v. Board of Education).
But regardless of how plausible, sincere, or even correct McConnell's view of the Fifth Amendment and Bolling is, I'd hate to be on the receiving end of a People for the American Way ad stating that "Bush nominee Michael McConnell believes that the federal government may establish Jim Crow, segregated schools." Or, "McConnell believes that the federal government is allowed to discriminate based on race, sex, or ethnicity." Either such ad, while not exactly fair, would be accurate.