My theory is based on my observation of election results, not on any evidence of why voters shunned candidates with mustaches. Watching election results on TV back in 2002, I noticed that every time a candidate with a mustache was on the screen it was because he had lost, and by the end of the night I was saying “oh, crap”!” every time I saw that the Republican candidate in a competitive race had a mustache.
I’ll give you a couple of examples. In 1996 and 2002, Democrat Tom Strickland ran against Wayne Allard for a U.S. Senate from Colorado; both times, Allard surprised many by winning 52%-47%. Strickland sported a mustache in both races, and has since shaved it off. And in 2002 Geoff Davis ran against Ken Lucas in Kentucky’s 4th District, and lost narrowly; he shaved his mustache in time for the 2004 election and he defeated Democrat Nick Clooney.
And, for the record, while I can’t grow a decent mustache myself (not that it would matter, since I don’t have enough real estate between my nose and the top of my lip to fit more than a very thin mustache anyways), soy ciertamente más macho que Fernando Lamas y Ricardo Montalbán. : )
I don’t believe we’ve had a President with facial hair since Taft. About 1/4 had facial hair of some sort. I think it’s a residue of the Roman Empire. They believed anyone with facial hair had something to hide.