Are Scientists Overwhelmingly Liberal Atheists?

According to a study of the opinions of scientists (described by endorendil, a commenter at EconLog):

Hmmm. Only 6% of scientists identify themselves as republicans, only 9% as conservative. You can look through the other tables, they all show that scientists largely take very un-libertarian and anti-free market viewpoints - much more than the public. Even those that don't work for universities. Remarkable is also how irreligious scientists are. Maybe that's why they don't buy into libertarianism or the free-market dogma.

On the other hand, the study also says:

The survey of scientists was conducted online with a random sample of 2,533 members of the American Association for the Advancement of Science (AAAS), from May 1 to June 14, 2009. AAAS is the world’s largest general scientific society, and includes members representing all scientific fields.

Maybe the conclusion is not that scientists tend to be liberal atheists but that members of an organization with vague goals and a leftist reputation tend to be liberal atheists. (That might also explain the results discussed here.)