Crowd-funding markets have recently emerged as a new source of capital supporting entrepreneurial ideas and ventures. In these markets, any individual is capable of proposing an idea, and interested others can then contribute funds in support of it. Given the recency of crowd-funding's emergence, participants' behavior in these markets is not yet well understood. From a social influence standpoint, these markets are unique because the timing and amount of others' prior contribution decisions are publicly observable. This observable information about prior contributions is therefore likely to have an influence on later contribution decisions. We empirically examine this notion in a crowd-funded market for online journalism. Bearing in mind that prior literature has identified online journalism as a form of public good, we find that funders in this marketplace treat one another's contributions as substitutable, a behavior that may be indicative of free riding. Practical and theoretical implications are discussed.