How influential was James Buchanan among libertarians?

Nancy MacLean's "Democracy in Chains" portrays the late economist James Buchanan as a central figure in the modern libertarian movement. An individual can be influential in different ways; he can be an institution-builder, inspire strategy, or directly influence other activists and movement intellectuals with his ideas. MacLean suggests that Buchanan was a supremely important institution-builder and strategy-inspirer, though I think she greatly exaggerates his role in both spheres.

But what of his direct influence on activists and movement intellectuals? As I noted in my first post on the book, my impression is that Buchanan was a peripheral or tangential figure in the development of modern libertarianism. It eventually occurred to me that there is at least one objective contemporary indicator that I am right.

In 1988, Liberty Magazine surveyed its readers regarding which important figures influenced their political views. Liberty was a small-circulation libertarian magazine that, unlike the "outreach" Reason magazine, was written to appeal to activist libertarians, the sort of people who work at think tanks, who are active in the Libertarian Party, or who promote libertarian causes like drug legalization. It wasn't a scientific survey but still provides some interesting data.

Buchanan won the Nobel Prize for Economics in 1986. MacLean claims that this "advanced the cause as nothing else had to that point." Strange that hard-core activist libertarians didn't notice. The editors explained how they chose the names on the survey list: "The names were chosen during the editorial meeting attended by Cox, Bradford, Holmes and Virkkala. An attempt was made to include on the list the most important contributors to libertarian thought, as well as figures believed by the editors to be influential among libertarians, and some individuals about whose influence that the editors were simply curious." James Buchanan wasn't on the list.

This could have been an oversight, but apparently not. Readers wrote in several names multiple times, including such now-forgotten figures as Robert Ringer, and even Buchanan's sometime collaborator, Gordon Tullock. Buchanan wasn't among the write-ins, either.

For the curious, the most influential modern libertarians, in order, were Ayn Rand, Murray Rothbard, Ludwig von Mises, F.A. Hayek and Milton Friedman. Note that contrary to MacLean's (almost entirely undocumented) suggestion that libertarianism was motivated to a large degree by Southern hostility to desegregation in general and Brown v. Board of Education in particular, none of these figures were Southerners, 60 percent of them were European refugees, 80 percent (all but Hayek, who had Jewish relatives) were Jews, and all lived in Chicago or New York.

It's also worth noting that despite MacLean's tracing of libertarianism's "lineage" to John Calhoun, he also—unlike other historical figures such as Locke, Jefferson and abolitionist Lysander Spooner—does not appear on the list.