One of the great things about Wikipedia is that not only can anyone edit it, anyone can get a sense of who has edited it by looking at the record of changes and connecting those changes to the IP address resposible for the edit. Buzzfeed's Andrew Kaczynski went through the histories of Wikipedia pages for members of the House and put together a list of edits made from the IP address that congressional staffers share.
For example, someone logged in from the congressional IP address removed Rep. Gregg Harper's (R-Mississippi) remark that he hunted "liberal, tree-hugging Democrats." The entire "controversies" section on Rep. Bennie Thompson's (D-Mississippi) was removed via a congressional terminal. Not every edit was a deletion. Reps. Mike Honda (D-California), Tim Huelskamp (R-Kansas), Richard Nugent (R-Florida), and Adam Smith (D-Washington) all had lengthy additions made to their Wikipedia pages. Now if only someone would create a Wikipedia page about members of Congress whose Wikipedia pages have been edited from within the halls of Congress.