Although people prefer to associate with winners, there is also a strong desire to support the lovable loser or underdog. In 4 studies, we demonstrate the underdog effect and its delimiting conditions. In Studies 1 and 2, participants rooted for the underdog in judgments of athletic, business, and artistic competition. In Study 3, participants watched animated clips of struggling and nonstruggling geometric shapes. The results showed that participants showed more rooting, sympathy, and identification with struggling shapes than with nonstruggling ones. Study 4 identified conditions under which people abandon the underdog, showing that participants rooted for the underdog only when both self-relevance and consequences were high. Theoretical implications of these findings are discussed.