Minor party candidates are quite common in modern democratic elections, but we know relatively little about the decision-making process of minor-party supporters. An extensive panel dataset is used to examine the individual-level dynamics of Nader support in the United States during the 2000 presidential election campaign. A multinomial logit model is estimated to analyse the factors related to a Nader supporter's decision to switch support to Gore, to switch support to Bush or to remain loyal to Nader from one interview to the next. The Nader supporters most likely to switch to a major-party candidate were the most politically aware, partisans, those concerned about policy outcomes and respondents in competitive states. Nader supporters were also more likely to abandon the candidate at the ballot box rather than earlier in the campaign. These findings challenge existing expectations about campaign dynamics and appear to reflect strategic calculations on the part of Nader supporters.