Compactifications of character varieties and skein relations on conformal blocks

Let M_C(G) be the moduli space of semistable principal G-bundles over a smooth curve C. We show that a flat degeneration of this space (Formula Presented.) associated to a singular stable curve (Formula Presented.) contains the free group character variety (Formula Presented.) as a dense open subset, where g = genus(C). In the case (Formula Presented.) we describe the resulting compactification explicitly, and in turn we conclude that the coordinate ring of (Formula Presented.) is presented by homogeneous skein relations. Along the way, we prove the parabolic version of these results over stable, marked curves (Formula Presented.).