When do legislators decide to get involved in the rulemaking process? The rulemaking literature has mostly focused on understanding the role of interest groups in the notice-and-comment period. However, we know very little about legislators' participation in the creation of rules by bureaucrats and how it aligns with interest groups. Using data from the Environmental Protection Agency, this paper shows that members of Congress are more likely to comment on a proposed rule after receiving campaign contributions from an interest group that has an interest in the same rule. This relationship is strongest for members with lower vote shares, suggesting that electorally vulnerable legislators are more responsive to their donors. Further, I find evidence that the comments of legislators and their donors are similar in content, compared to those of non-donors. These results broadly indicate that there is an understudied channel through which contributions can indirectly affect policymaking.