Although crowdfunding has received a great deal of attention, few studies utilize a theory-oriented approach to understand what lead to crowdfunding success. In this paper, we employ signaling theory to explore the secret of the fundraising success. We propose that signals from creators and project descriptions influence the fundraising success, and these effects are moderated by backers’ comments and creators’ replies. To test our hypotheses, we collected objective data of 400 successful crowdfunding projects from the largest crowdfunding platform in China. The results indicate that creators’ previous creator experience, backers’ comments, and creators’ replies positively affect fundraising success. We also find partial support for the proposed moderation effects.