This article examines the behavior of voters who decide on their presidential candidate preferences within the final two weeks of the presidential campaigns. Relying on data from American National Election Studies (ANES) for elections, between 1972 and 1988, we demonstrate that late deciders are different from other voters in a variety of respects. They are less involved politically and far less predictable in their behavior than other voters. More significantly, we find that the candidate preferences of late deciders are not determined by the conventional political forces that motivate other voters. Rather, the choices that late deciders make appear to be nearly random in character. The implications of these findings for the analysis of electorates are discussed.