Record numbers of women were elected into office in the US in recent years, and campaign financing may have contributed to their successes. This raises two questions: Is there a gender gap in campaign strategy and spending? And if there is, does it have an impact on election outcomes? Using a new dataset that includes itemized campaign expenditures for the almost 3,500 candidates who contested a House election between 2012 and 2020, we report little evidence of a gender gap in candidates’ campaign spending, but we find some differences in the effects of communications spending on women’s and men’s electoral performances. Female challengers, in particular, must spend more to achieve the same results as men. The findings provide yet another indicator that congressional elections are an uneven playing field, and women must work harder than men to get elected. The results have implications for elections, representation, and public policy.