Candidate personality traits have long been recognized as influential in the determination of voting choice. However, little is understood of how the perception of candidates' traits influences different categories of voters. Based on a large-scale electoral-panel survey (ITANES, ITAlian National Election Studies), the present study investigated whether the voting choice of early and late deciders differentially relied on candidate traits. Results showed that after considering the influence of ideology and economy assessment, candidate traits still influenced the voting choice of early deciders and, even more, of late deciders. However, while early deciders took into account both incumbent and challenger traits, late deciders mainly relied on incumbent traits. Political sophistication moderated this effect, with high-sophisticated early deciders relying even more on the challenger, and low-sophisticated late deciders relying even more on the incumbent. The distinction between incumbent and challenger is discussed as a key variable in explaining the role of candidate traits in the choice of voters differing as to voting decision time and political sophistication.