party affiliation or, for those already affiliated, assure their turnout. However, such communication is effective only if voters have formed preferences and get to choose among a stable set of parties offering clear policy alternatives. The relative absence of such conditions in many transitional party systems means that voters cannot evaluate electoral alternatives and parties cannot effectively solicit electoral support. As a result, politicians in transitional democracies rely just as much on coordination strategies as they do on electioneering strategies.
Implications for Theory Development: The numerous variables suggested by literature vary tremendously in their theoretical potential. Institutions clearly have the greatest theoretical potential. The specific procedures affecting strategic voting are few in number, well conceptualized and readily quantified. These procedures also are not easy to change, and, if they remain unchanged, have effects remains constant across time and only vary across cases. Coordination strategies have a more limited theoretical potential. Their potential stems from the fact that are clearly anchor in individual actors, have well developed causal mechanisms and also appear to be invariant across time. Their limitations stems from the fact that they are very numerous, unevenly conceptualized, subject to important interaction effects and still lacking in extensive cross-national data. Historical factors clearly have the smallest theoretical potential; they vary not only more across cases but their effects also is changing across time. This change can be increasing in the form of increasing returns or diminishing as legacies fade away. This being the first case study, that pays equal attention to all three of these factors should give us a preliminary idea of how much each mattered in postwar Germany. This insight combined with the theoretical potential of individual factors gives some clues about theoretical potential there is, that what the prospects of explaining the development of party system in terms of systematic co-variation of causal variables.
II. INSTITUTIONAL FACTORS
How well do institutional accounts explain the formation of the Germany party system ? Table 2 displays for Germany some of the data that institutional explanations use for their large n, cross-sectional analysis. There is much of the Germany data that the latter’s more general findings. Fragmentation dropped very quickly, suggesting voters