"Winter Kills," an extravagantly kitschy movie version of one of Richard Condon's Jacobean conspiracy thrillers, was recenlty salvaged by a backer who succeeded in raising enough to complete and release the film, which had been junked after three months of shooting a couple of years ago.

Its $7-million budget, however, looks as unretrievable as the $20 million squandered on "Hurricane." It has only marginally entertaining aspects, like the sight of Elizabeth Aylor (in an unbilled appearance) wearing a curly, cherry-colored wig while pretending to be The Most Fashionable Madame in Washington.

The original backers must have overlooked the consistent failure of similar projects over the past decade: "Castle Keep," "The Sporting Club," "WUSA", "Executive Action," "The Aprallax View," "The Domino Principle." Perhaps it also has been forgotten that the witty film version of Condon's "The Manchurian Candidate" adapted by George Axelrod and directed by John Frankenheimer 17 years ago was not a box-office hit. As Axelrod engaginly pointed out in a recent interview, "It went from failure to classic without ever passing through success. Like me."

"The Manchurian Candidate" preceded the assassination of President Kennedy, a circumstances which freed it from the lurid, semi-pornographic hindsight which colors "Winter Kills," a melodramatic orgy of evil-minded speculation inspired by the assassination.

Nick Kegan, the protagonist of "Winter Kills," is the surviving halfbrother of the assassinated President Tim Kegan, shot down in a motorcade in Philadelphia in 1960. Their father, a greedy, vulgar, hedonistic oldy tycoon known as Pa Kegan, controls a global financial empire. While supervising one of his father's oil-drilling operations in the Orient, Nick Learns of the existence of a man who claims to have been Timhs "real" assassin-looked in the findings of the prestigious Pickering Commission Report.

Nick hears the man's dying confession and finds the alleged murder weapon still hidden where indicated in a Philadelphia office building. He loses it-and corroborating witnesses-almost immediately when distracted by a mysterious blond bicyclist who appears to be chewing some exotic flavor of explosive bubble gum. The rest of the scenario is devoted to labyrinthine detours and wild-goose chases which pretend to circle ever closer to the Mr. Big behind the dastardly deed.

Some previous exposure to Condon's conspiratorial plots and Oedipal conflicts will take virtually all the mystery out of the ostensible search for the guilty party. The casting and performances exaggerate the foregone conclusion with cartoonish contrasts: Jeff Bridges as a soft, naive, ineffectual Nick set against John Huston in a hammy caricature of unscrupulousness as Pa.

The story is fairly repulsive to begin with, Condon takes a peculaiarly nast satisfaction in his favorite blueprint for treachery, where the world is controlled by grasping matriarchs or patriachs wantonly sacrificing their offspring to secure political and monetary advantage.

Writer-director William Richert adds to the unpalatability by trying to outdo Condon at his own hyperbolic games.