Looks like the Hatch Act doesn’t apply to rats.
It provides that persons below the policymaking level in the executive branch of the federal government must not only refrain from political practices that would be illegal for any citizen but must abstain from "any active part" in political campaigns, using this language to specify those who are exempt:[3]
(i) an employee paid from an appropriation for the Executive Office of the President; or
(ii) an employee appointed by the President, by and with the advice and consent of the Senate, whose position is located within the United States, who determines policies to be pursued by the United States in the nationwide administration of Federal laws.