This authoritative source for students, scholars, journalists, and interested observers sheds light on the small number of states that matter most in American presidential politics. David Schultz and Christopher Miller bring conceptual clarity to the term "swing states," which despite the media's frequent use of terms like "battlegrounds," "bellwethers," and "swing states," has remained poorly understood. Through examination of these states and the factors that make them "swing" this volume addresses a significant gap in the scholarly literature in a way that will be instructive for scholars and student of elections and state politics as well as the media and the public as they seek to understand the factors shaping the vote for president in these states, and the consequences for the conduct of presidential campaigns and ultimately for the outcome of presidential elections. The fourth edition continues what has made the previous editions successful, and improves on them in a few key ways. First, the contributors focus on just the seven states (plus the two partial swing states of Maine and Nebraska) now seen as being the key battlegrounds that define presidential elections, leaving out the states of New Hampshire, Ohio, and Minnesota which have become more reliably partisan. Second, the new edition employs a new co-editor who not only brings extensive scholarly experience but is also well networked with journalists and is attuned to their needs. Third, the new edition will be published after an election where all the swing states cast their electoral votes for the same candidate-Donald Trump. Wither the swing states?, some might ask. Absolutely not, this volume responds.