Political scientists have long painted American voters dependence on partisan cues at the ballot box as a discouraging consequence of their overall ignorance about politics. Taking on this conventional wisdom, Jeffrey D. Grynaviski advances the provocative theory that voters instead rely on these cues because party brand names provide credible information about how politicians are likely to act in office, despite the weakness of formal party organization in the United States. Among the important empirical implications of his theory, which he carefully supports with rigorous data analysis, are...