If satire is what dies on a Saturday night, then political-satire movies are what die on Fridays. Maybe we're used to the TV topicality of "The Daily Show with Jon Stewart" or "Real Time with Bill Maher," whereas movies are months in the making, turning their current events into history. Yet successful satire needn't be topical--witness Network, Election, Dr. Strangelove--because some verities are timeless. And since when, after all, hasn't there been a populist saying, "Throw the rascals out"?

In writer-director Barry Levinson's comedy/drama/thriller--no less a jumble than our political conventions--that populist is Tom Dobbs (Robin Williams), a political comic in the vein of a Stewart on speed. He's running as a vaguely defined independent candidate on a platform of accepting no campaign contributions that would make him beholden to lobbyists and special interests. With his manager, the anything but H. L. Mencken-like Jack Menken (Christopher Walken), his associate Eddie Langston (real-life political comic Lewis Black) and a couple of staffers, he rides the road in a red-white-and-blue bus that's carried him to the ballot in 17 states. So far it's all as plausible as Ross Perot or Ralph Nader.

So is, sadly enough, the concept of computerized voting machines that, in contrast with every ATM in the world, won't provide a paper receipt. Unlike activists' allegations against the real-life Diebold, Inc.--an ATM maker that won't provide paper proof, and whose CEO, Walden O'Dell, wrote in an August 2003 Republican fundraising letter that he was committed "to helping Ohio deliver its electoral votes to the President"-the computers that give Dobbs the election don't do so from ideology but from simple greed and corner-cutting. By the time Eleanor Green (Laura Linney), a programmer at the movie's fictional voting-machine company, discovers a glitch in the system, it's too late to fix. And rather than give up its windfall mega-business and tell the states to haul out their trusty old-fashioned voting machines, the company tells Eleanor to keep mum.

Eleanor, having apparently never seen Silkwood, blithely goes home, where she's attacked but not killed. Opting to destroy her credibility instead, company founder Hemmings (Rick Roberts) and legal chief Stewart (Jeff Goldblum) take a high-tech, chemically based route that only turns more physically nefarious after Eleanor escapes to Washington, D.C., to try to tell Dobbs the truth.

Here the film goes on a credibility roller coaster--astute in its depictions of Secret Service flankers and police escorts, but, in issues of presidential security and debate-handling (just turn off his microphone, genius), much more cavalier than the far less leisurely produced weekly television series "The West Wing." With a premise requiring the leap of faith that this one requires, every credible flake that drops lands with a thud.

If you look the other way and go with it regardless, Man of the Year can be an idealistic pleasure, saying things straight out that, however simplistic to fit the constraints of running time, need to be said. Levinson seems to have let Williams off his improv leash, letting him fire his jibes with clever but accessible abandon. If the comedian is perhaps a bit too on when in private and minces less than authoritatively in some of his femmier routines, he makes up for it with the humor of moral outrage. Except for his scene addressing Congress while dressed as George Washington. Even if he didn't look like Mrs. Doubtfire in drag, it's farcically at odds with a movie that's funny, but isn't comedy.