Plant performance is predicted to decline toward range edges, due to the effects of geographic or climatic marginality. Alternatively, global change can create directional effects of range position, with declining performance toward equatorial or warm range edges. Although prior work has found support for these patterns in widespread species, few studies have tested whether they apply to rare or narrowly distributed species. Narrow-ranged species inherently experience less variation in range position or climate compared to widespread species, but conversely may be more sensitive to what variation does exist. In this study, I quantify range-wide variation in occurrence, abundance, and fitness for three federally endangered plant species endemic to granite outcrops in the Southeastern United States. I first test for effects of range position, building on traditional methods of defining a species’ range center. I then test for effects of multiple climate variables as well as overall climatic marginality by comparing local performance to the predicted habitat suitability obtained from Species Distribution Models. The results of this study will inform how broad-scale geographic and climatic drivers influence the fitness and persistence of three rare endemics of conservation concern.