Why do Republican politicians promise to rein in government, only to face repeated rebellions from Republican voters and media critics for betraying their principles? Why do Democratic politicians propose an array of different policies to match the diversity of their supporters, only to become mired in stark demographic divisions over issue priorities? In short, why do the two parties act so differently-whether in the electorate, on the campaign trail, or in public office?

Asymmetric Politics offers a comprehensive explanation: The Republican Party is the vehicle of an...

Why do Republican politicians promise to rein in government, only to face repeated rebellions from Republican voters and media critics for betraying their principles? Why do Democratic politicians propose an array of different policies to match the diversity of their supporters, only to become mired in stark demographic divisions over issue priorities? In short, why do the two parties act so differently-whether in the electorate, on the campaign trail, or in public office?

Asymmetric Politics offers a comprehensive explanation: The Republican Party is the vehicle of an...