Compromise is critical to democratic policymaking, but it can be hard to find on Capitol Hill. In this era of routine legislative gridlock, however, some lawmakers do still cross the aisle. In Dealmakers, David C. Barker, Andrew M.O. Ballard, and Christopher Jan Carman examine why they do—and why they tend to be Democrats. The answer, the authors contend, comes down to voter differences in personality and values. Specifically, they argue that empathetic traits and values ...