The first column of Table 4 supports expectations about the role of party constituencies
and state partisanship on senators’ representativeness. Specifically, senators in states with more
extreme party identifiers (relative to the state’s average ideology) are drawn farther from the
center of the state’s ideological distribution. Likewise, senators in states where their parties are
more dominant in the electorate are less representative of their states’ average citizens.
Partisanship also plays a role in representativeness through the party affiliation dummy variable.
Compared to their Republican counterparts, Democratic senators much more closely reflect their
states’ average preferences. The final significant influence on representativeness is senators’
electoral marginality. States receive greater ideological representation when their senators have
won their most recent elections more easily. On the other hand, representativeness does not
appear to depend on whether or not senators are serving in their first terms.
[Table 4 about here]
Because the earlier analyses reveal differences between Democratic and Republican
senators, we proceed to estimate the representativeness model (minus the party affiliation
dummy) separately for members of each party. These results are displayed in the second and
third columns of Table 4 and confirm that senators from the two parties exhibit distinctive
patterns in their representativeness. Republicans are sensitive to the ideologies of their own
partisans and to the partisan composition of their states, with more extreme partisans and more
favorable partisanship drawing them away from the center of the states’ ideological distributions.
Democrats, on the other hand, appear unaffected by the nature of their party constituencies and
by the relative number of citizens identifying with their party. Unlike Democrats, Republicans
also vary in their representativeness by their length in office. Republicans serving in their first
term during the 1988-1992 period more closely match their citizens’ average preferences than do
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