Political professionals and scholars maintain that raising money early in the election season is critical to a successful campaign, having downstream consequences on a candidate’s future fundraising potential, the stiffness of competition she will face, and her likelihood of electoral victory. In spite of early money’s perceived importance, there is no common operationalization for money as “early.” Moreover, existing measures often fail to reflect definitional aspects of early money. In this paper, we first lay out a theoretical framework regarding the utility of early campaign fundraising for candidates. We argue that early fundraising can be expressed as two conceptually distinct quantities of interest centered on either a candidate’s own fundraising performance (candidate-centered) or her fundraising performance relative to her electoral competitors (election-centered). We next lay out steps for operationalizing candidate- and election-centered measures of early fundraising. Lastly, we demonstrate that both our proposed measures for early campaign fundraising are predictive of a candidate’s future fundraising and electoral success. By putting forward a set of best practices for early money measurement and, additionally, producing off-the-shelf measures for early fundraising in U.S. House elections, we fill an important gap in scholarly research on the measurement of money in politics.