We argue that state legislative politics is qualitatively different from national congressional politics in the extent to which it focuses on localized and geographically specific legislation salient to subconstituencies within a legislative district. Whereas congressional politics focuses on casework benefits for individual constituents, state legislative politics is more oriented to the delivery of localized benefits for groups of citizens in specific areas within a district, fostering a geographically specific group connection. A primary way to build such targeted geographical support is for members to introduce particularistic legislation designed to aid their specific targeted geographical area within the district. We argue that this is primarily a function of electoral rules. Using original sponsorship data from U.S. state houses, we demonstrate that greater district magnitude and more inclusive selection procedures such as open primaries are associated with more particularism. Our findings provide strong support for a voter-group alignment model of electoral politics distinct from the personal vote/electoral connection model that characterizes U.S. congressional politics and is more akin to patterns of geographically specific group-oriented electoral politics found in Europe and throughout the world.