What factors affect client perception of vendor preference in a crowdsourcing marketplace? We approach this question from two theoretical perspectives in this study. First, extending the knowledge of e-commerce transaction, we propose the concept of vendor-task fit in this study and test its relationship to vendor preference. Second, we posit that swift trust also influences client decisions. Our research model is being tested via a field study of the leading Chinese-based crowdsourcing platform zhubajie.com. Our results show a full mediation role of swift trust for the effect of reputation on vendor preference and partial mediation role for the effect of competence on vendor preference; however, vendor-task fit is found to have a slightly less important role influencing vendor preference compared to swift trust. Our contributions will shed light on the phenomenon of crowdsourcing, especially, vendor preference issues.