Percentage difference in drag between a sphere and a prolate spheroid of identical volume at Re << 1. As the ratio of length to diameter of the spheroid increases (i.e. the shape elongates) there is an initial decrease in drag, but this difference only results in drag for the spheroid dropping to a minimum of 95.66% of that of the sphere.
Humphries et al. BMC Evolutionary Biology 2008 8:319 doi:10.1186/1471-2148-8-319