Despite their recognized importance, the inherent opacity of intra-party institutions limits scholarly understanding of how parties share power internally. We advance knowledge in this area by studying how parties allocate list positions to different factions. We develop a theory of intra-party bargaining in which list positions shape the mobilization efforts of party activists in different factions. Our results allow us to link observable patterns in list allocations to the importance of consensus in intra-party negotiations. We empirically evaluate these predictions using data from Norwegian municipal elections. We exploit a wave of municipal mergers to identify candidates' geography-based factional affiliations. In line with our theory's functionalist logic and consensus-based bargaining, smaller factions are over-compensated in `safe' list positions. While we also find a slight over-representation in the contested ranks, the relationship between size and resources is much closer to proportionality, as predicted by our theory.