This article examines party sorting, elite cue and ideological polarization accounts of polarization dynamics. The study tests their differing expectations about trends in redistributive ideological polarization and partisan polarization in the British case using repeated cross-section and panel data. The authors reject party sorting accounts, which require ideology to be stable and changes in party support to drive partisan polarization, because they find that ideology trends with elite polarization and that ideological change causes partisan polarization. The authors reject elite cue accounts, which maintain that it is mainly partisans’ ideology that follows elite polarization, because they find virtually identical trends for initially ideologically similar non-partisans too. The study thus finds support for an ideological polarization account in which changes in elite polarization are associated with general changes in citizen redistributive ideology.

We analyze the effect of redrawn constituents on incumbent vote shares in Georgia U.S. House elections from 1992 to 2006. The Georgia General Assembly redrew the congressional boundaries for the 2006 midterm and the new lines redistributed approximately 31% of residents into districts with a different incumbent than the one representing them in 2004. With the use of Voting Tabulation District (VTD) data, we use a hierarchical model to evaluate the effect these redrawn constituents had on their new incumbent's vote share. We find a consistent pattern: both Democratic and Republican incumbents experienced significant reductions in their vote shares as a consequence of the redrawn VTDs placed in their districts. The short-term political climate featuring a national Democratic tide and a simultaneous statewide trend favoring the Grand Old Party (GOP) helps to explain this finding. With offsetting partisan conditions, the incumbency advantage came to the fore as Georgia U.S. House members, irrespective of party affiliation, performed better among the constituents they retained prior to redistricting. Our findings for the 2006 election run counter to the significant Republican redistricting advantage prevailing in Georgia congressional contests from 1992 to 2004.