Crosslinkable polymeric compositions comprising (a) 10 to 99 weight percent of an ethylene-based interpolymer having the following properties: (i) a density of 0.93 g/cm3 or less, (ii) a high-shear viscosity (V100) at 190° C. and 10% strain of 1,200 Pa-s or less, and (iii) a shear thinning ratio (V0.1/V100) at 190° C. and 10% strain of at least 8; and (b) 0 to less than 10 weight percent of a filler, where the ethylene-based interpolymer is not prepared in a high-pressure reactor. Such crosslinkable polymeric compositions may be employed as insulation layers in flexible power cables.