I found this growing in southern Oconee Co. It receives morning shade with full sun the rest of the day. It is a small population of 15 to 20 individuals over a 3 x 5 meter area. Plant height is 15 to 30 cm depending upon maturity with pubescent stems; the peduncle adds another 10 to 15 cm of height. The foliage is 10 to 12 cm in length with alternate arrangement. Flowers are white to pink and papilionaceous in form; it was difficult to determine if buds or spent flowers (seen in detail image 1) were red. [Sorry for the poor photos, I was working with a new camera.] I suspect it is Tephrosia, but unsure.
I would say it is certainly a Tephrosia – and using the key, it seems to fit Tephrosia hispidula the best – I am not 100 % positive on the species, though. Tephrosia hispidula flowers come out white, then turn various shades of pink to red with age, but so do the other possibilities – T. florida and T. spicata. Pictures on the internet seem to indicate that your species is actually Tephrosia spicata, and that is the most common species in SC [other than Tephrosia virginiana which it certainly is not]. I would probably go with T. spicata, because I could not see all the technical characters in the photos but it does look much like that one. – Steve Hill