After not seeing any hummingbirds for over two months, I took my hummingbird feeder down. Since I hadn't gotten one of those ant traps, the ants were, indeed, becoming a problem.
I did get an ant trap and figured I'd put it out when I hung the bird feeder in the spring. Little did I know that I would be using it a bit more quickly than that.
The day before my family came down (so the 21st of December), I was sitting backwards on the chair (that is, the chair faces into the living room, but it has the only windows in the room right behind it), and I noticed a hummingbird looking for blooms by the window. I quickly put water and sugar in the feeder and re-hung it outside. Sure enough, the bird easily found the feeder. Since then, I've been having a bird show up every day. This one isn't nearly as skittish as the other hummingbirds and has no problem with using the feeder while I'm doing yard work right next to it.
Thus, while this picture doesn't really look like I'm any closer than any of the previous photos I've taken (you can see them here and here), I'm using a 70mm lens instead of the 300. Which basically means that I was like 5' away from the bird instead of 12'.
Based on the apparent affiliation with the Texas Longhorns, I'm going to guess that this bird is a Rufous. Though it could be an Allen's Hummingbird.