Crowdfunding is regarded a financing mechanism that could improve the funding opportunities of businesses with a pro-social orientation. Indeed, it is assumed that on digital platforms, citizens are inclined to provide more support to projects with a social benefit than to those without such an orientation, with significant ethical implications for the common good. Yet, extant empirical evidence regarding such a claim is still inconclusive. To advance this discussion, the present paper analyzes the conditions that influence crowd support for projects displaying a pro-social orientation on a reward-based crowdfunding platform. To build our hypotheses, we adopt the lens of framing theory, and we relate it to the digital context. Beginning from the premise that, on crowdfunding platforms, information about projects has a hierarchical structure, we argue that a project's success crucially depends on how much its proponent emphasizes the pro-social cues within this structure. Moreover, we propose that because pro-social cues demarcate a project over others, the effectiveness of pro-social framing is enhanced when the number of projects on the platform, i.e., its crowdedness, increases. Logit estimates on 8631 Kickstarter projects indicate that pro-social framing is positively associated with success as we expected, yet only when it is moderately emphasized. Further, we find that crowdedness on the platform positively moderates the effect of pro-social orientation on success.