AbstractSelf‐presentation in Congress is more nationalized, with digital constituencies on platforms such as Twitter offering new reputation‐building opportunities. Digital constituencies transform traditional expectations of constituent communication, challenging Richard Fenno's theory that representatives adopt an “expansionist” style with constituents during early, vulnerable phases of their tenure. In a digital era that encourages a more national approach, we question how Fenno's distinction between expansionist and protectionist phases of connecting with constituents applies to reputation‐building with digital constituencies. While electorally vulnerable senators still seek to expand their presentation among geographic constituents, digital platforms, such as Twitter, incentivize them to protect their reputation among a digital constituency. We analyzed senators' Twitter communications from 2013 to 2023. We find the electoral vulnerabilities of Fenno's expansionist local model are associated with a protectionist model of engagement with digital constituencies on Twitter. Our study sheds light on the significance of online reputation management and its implications for representing a media‐influenced, modern Congress.