In this paper we present high-frequency (95 GHz) pulsed electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) measurements on the nitrogen (N) donor in 4H-SiC (k site) and 6H-SiC (h, k(1) and k(2) sites). From the hyperfine interaction of the unpaired electron spin of the donor with the (13)C and (29)Si nuclei, the distribution of the electronic wave function of the N donor is determined. The main part Of the spin density in 4H-SiC is located on the Si sublattice and the wave function contains a relatively large fraction of Si p-character. For the three sites in 6H-SiC the main part of the spin density is located on the C and the wave function is built mostly of s like C atomic orbitals. Comparing the three sites in 6H-SiC, the h site wave function has the largest delocalization and is most isotropic. The k(2) site wave function is most localised and less isotropic. The difference in behaviour of the wave function in 4H and 6H polytypes seems to find its origin in the difference in their conduction-band structure. Our results indicate that the conduction-band minima in 4H-SiC are mainly Si-like whereas in 6H-SiC the conduction-hand minima are most C-like.