Ratfucking is an American slang term for political sabotage or dirty tricks. It was first brought to public attention by Bob Woodward and Carl Bernstein in their Pulitzer Prize winning book, All The President's Men.
Former Committee to Re-elect the President (CREEP) staffer Donald Segretti told the authors, during their investigation of activities leading to the Watergate break-in on June 17, 1972, of a program of orchestrated political sabotage by supporters of Richard Nixon against Nixon's political opponents. These included, but were not limited to, cancelling meeting-hall reservations just prior to rallies, releasing false press releases or "leaked documents" in the name of political opponents, spying on rival campaigns, stuffing ballot boxes, ordering vast quantities of food for delivery in the name of rival campaigns, conducting deceptive or offensive get out the vote phone canvasses, push polls, and similar activities.
There is a fine line between this type of political sabotage and more clever political pranks, such as those practiced by Dick Tuck, who was perhaps the model who drove Nixon to hiring agents against his opponents.