Partisan Polarization and the Effect of Congressional Performance Evaluations on Party Brands and American Elections

Scholars of political parties and elections around the globe have devoted extensive study toward understanding how party polarization affects the criteria voters use to determine their party preferences in elections. In American politics, previous empirical research suggests that congressional job performance ratings do not affect public attitudes toward parties and therefore have no significant ramifications for the electoral fortunes of parties. Building on the existing literature from American and comparative traditions, I demonstrate that congressional performance evaluations can be important for American parties and elections, but this depends on the extent of party polarization in Congress. First, when congressional parties are more distinct, congressional performance evaluations have a greater effect on the relative favorability of the majority party brand: when citizens like how Congress is performing under the leadership of the majority party, this boosts the favorability of that party overall. Second, because partisan polarization increases the effect of congressional performance evaluations on party brand favorability, partisan polarization also increases the role played by congressional performance evaluations in a variety of elections outside of Congress. These results inform our understanding of public opinion, parties, and elections, both in the U.S. and from a comparative perspective.