Throughout American history, presidential elections have meant choosing not just a winner, but also a loser. As a new book suggests, those who have lost their shot at the highest office in the land have sometimes gone on to retreat from public life, but often they have gone on either to make major achievements or to leave a significant intellectual or political legacy. A taxonomy of presidential losers suggests some possibilities for the current Republican candidates, who, thanks to the current electoral media frenzy, stand to capitalize on their prominence even if they don’t make it to the White House.