GOOF ALERT! With eyes wide shut, I described this bird as an Allen's male in my original posting to my local bird listserv, but it obviously couldn't that, as a friendly expert pointed out. An adult male bird, either Rufous or Allen's, would have a bright orange gorget, a piece of knowledge I had somewhere in my mind, but managed to suppress as I formed and posted my identification.

This bird's gorget is mostly pale, with a dark spot in the center, which means it is an adult female, either Rufous or Allen's. Here's another picture of the same bird, showing more of the sometimes-decisive tail feathers, with an explanation of why this one can't be identified to species and so has to be left as a Rufous-or-Allen's adult female: http://www.pbase.com/tgrey/image/155423338 .