“Campaign finance reformers” often depict (private sector) funding of political ads as an overwhelmingly influential factor in elections.
But there are many ways that people and institutions influence election outcomes. Government agencies have numerous means of trying to influence the political sphere.
Now the Washington Post reports that the US Postal Service gave time off and other benefits to Postal employees who campaigned for Hillary in the 2016 presidential election. See here.
This practice of the Postal Service apparently reached a massive scale.