Hard to tell from these photos. Is the breast a bright red? Or more of an orange color? If orange, could be Baltimore Oriole, although I suspect that since they're on a humming bird feeder, they're smaller than the Oriole.
Grosbeak might be another possibility. That's another largish bird though too.
Both would be about 8.25 inches long.
I'll keep looking in my Sibley's and see if anything else looks closer, but it would help if you could tell us the approximate size, and any other distinctive markings, etc.