The Consequences of Neglecting the Median: Major Party Vote Shares in Seven Western Democracies Robin Best Syracuse University March 24 th, 2007

The Project To examine the effects of major party positioning on the Two-Party vote share. Two-Party vote share = total % of the vote received by the two major parties. Motivation: Party systems in virtually all advanced democracies have become increasingly fragmented over the post-WWII era. The total % of the vote share received by the two major parties has often significantly declined over the post-WWII era.

The Effective Number of Electoral Parties by Time Period

Red Line: Two-Party Vote % Black Line: ENP

Polarization and Bracketing McDonald 2006; McDonald et. al In the long-term, representation is accurate and responsive, even when parties diverge. Long-term representational prospects are best when the two-parties bracket the median voter on each issue. I focus on the short-term consequences of party polarization and bracketing: How does the failure of major parties to converge (i.e. party polarization) affect the Two-Party vote share? How does the failure of major parties to bracket the median voter affect the Two-Party vote share?

Party Polarization How would party divergence affect the Two-Party vote?  Downs: Converging is the vote-maximizing strategy.  But maybe not…Parties may benefit when they diverge, capitalizing on valence, voter biases, etc.  Converging may lose votes to smaller, more extreme parties.  McDonald et. al.: In the short run, incongruence is larger when polarization is high. If voters care that the two major parties aren't very close to their policy preferences, we may see voters supporting alternative parties.  Polarization should decrease the Two-Party vote in the presence of a small centrist party (e.g. the Liberal Democrats in the U.K., the FDP in Germany).

Bracketing Failing to bracket the median voter on an issue may increase support for smaller parties and (conversely) decrease support for the two- major parties. Two forms of “failure to bracket” 1) Both major parties position themselves on the issue, but fail to bracket the median voter. 2) At least one of the two major parties fails to position themselves on the issue.  Research on new party entries suggests new parties are likely to emerge and receive votes when an important issue is being neglected by one or more major parties (e.g. Hug 2001).  Importance of New Politics issues.

Data and Measurement Dependent Variable: Total % of the vote received by the two major parties. Australia, Austria, Canada, Germany, Ireland, New Zealand, U.K., U.S., Polarization: the ideological distance between the two-major parties on the left-right dimension (CMP 2006). Bracketing: Failure of the two major parties to bracket the median voter on Welfare, International Peace, Planned Economy, Market Economy. # of New Politics issues where at least one of the two major parties fails to take a position (i.e. CMP coding of zero).

Expectations OLS Regression Dependent Variable: Two-Party Vote Share Independent VariableExpected Effect Two-Party Vote t-1 + Planned Economy- Market Economy- Welfare- Peace- # of New Politics Issues- Polarization+ Polarization*Center Party- SMD+

Party Polarization, Bracketing, and Two-Party Vote Share, ________________________________________________________________________ VariableCoefficient(Std. Err.) ________________________________________________________________________ Two-Party Vote t-1.40***(.09) Market Economy-.30(1.57) Planned Economy.68(1.06) Welfare-3.45**(1.80) Peace2.39**(1.09) # New Politics Issues.21(.21) Polarization.06**(.03) Center Party5.46*(4.16) Polarization*Center Party-.12**(.06) SMD5.09**(2.61) Constant-4.53(4.46) ________________________________________________________ N121*** p ≤.001, ** p ≤.05 *p ≤.102 R2.41 _____________________________________________________

Yellow Line: FPÖ left-right position Black Line: ENP

Party Positioning, Two-Party Vote Shares, and Party System Fragmentation Major party bracketing appears to matter little for (combined) major party vote shares. Issue salience to voters? Length of time of neglect? Major-party polarization appears to encourage fragmentation when there is a small centrist party, and limit fragmentation when there is not. Does this leave room for centrist parties to emerge? How might the positioning of other (smaller) parties matter for major party positioning, vote shares, and party system fragmentation? E.g. Austria