Wikipedia
The Tegenpartij (Counterparty, but also opponent) was a Dutch fictional political party, founded by Jacobse and Van Es, two vrije jongens (free guys, literally), played by Kees van Kooten and Wim de Bie. The Tegenpartij was the party for all Dutchmen who can no longer stand the Netherlands.
Van Kooten and De Bie were trying to fight the populist tendencies of some of the other parties with their parody, but things turned out a bit differently: the Tegenpartij became so popular that it might well have gained several seats in parliament if it had actually taken part in elections. The party was finally disbanded on May 10, 1981, just before the elections, because Jacobse and Van Es were shot at the Binnenhof, the center of Dutch politics.
Twenty-one years later, the Tegenpartij sketches once again became topical, because of their strong resemblance in parts to the rise of the right-wing political party Pim Fortuyn List.