Query: Is an "air-head" the same thing as an "empty-head," or are they different?

I hope this post doesn't get me in (too much) trouble . . .

An anonymous commentator (man or woman? -- I'd love to know), responding to my recent post Peña Nieto Bares All (http://mexicogulfreporter.blogspot.com/2012/01/pena-nieto-admits-i-was-unfaithful-and.html), today left a note observing that "The sad part is many Mexicans will probably vote for this air-head."

"Air-head" is a term I enjoy, and I'm glad to see someone else employ it, especially in a public forum referring to a male political candidate. I rarely use it these days, because I've been told it both "dates" me and brands me as sexist (unfairly so, in my opinion). As a young(er) man I commonly referred to not so bright members of the opposite sex as "air-heads." And I confess that not infrequently I found myself in the company of such women, because in those days a stunning intellect was not my primary criterion for asking someone out on a date. Now my tastes have changed considerably, of course . . . of course they have.

I also wrote another very popular post about PRI nominee Enrique Peña Nieto on Jan. 21, entitled "From an empty head, nothing comes" (http://mexicogulfreporter.blogspot.com/2012/01/santiago-creel-on-enrique-pena-nieto.html). Those were the words of then-PAN primary candidate Santiago Creel, who was soundly walloped (54%-6%) in the PAN internal election last Sunday (Feb. 5) by the party's new nominee, Josefina Vázquez Mota. When I translated Creel's exact words into English, I was dealing with the Spanish adjective hueco, which has a dictionary definition of hollow, vacant, vacuum-like, etc. A "vacuum head" struck me as a rather curious turn of phrase, and an "air-head" seemed to me to be appropriate only for a women. So I settled on an "empty head," ever mindful that a skilled translator's lodestar is to translate ideas and concepts, not words.

I thought I was faithful to what Santiago Creel said in his own language. But now I wonder. Are the terms interchangeable, and may a male political candidate -- a macho no less! -- legitimately be referred to as an "air-head"? Any suggestions would be welcome.