Despite evidence that women's political preferences differ from those of men, women are less likely to participate in political and social discussions on Twitter and other social media. Following recent evidence that in-person social support matters for women's political participation, women are hypothesized to form similarly supportive communities online. This paper tests this hypothesis using data from Twitter. The collected data comprises 451 hashtags on a broad range of (non-mutually exclusive) topics: social, gender, racial, LGBTQ, religion, youth, education, economic, health, COVID, climate, political, security, entertainment and lifestyle, and the Middle East and Northern Africa. The empirical results indicate that women are more likely to participate when the debate(s) feature female influential voices. This finding supports the potential role of mutual support in bolstering women's participation in important debates.