In “No,” an engaging political satire from Chile, “All the President’s Men” meets “Mad Men.” It’s a funny look at the way the media warp public opinion, and a curiously hopeful one. The film doesn’t agonize over the debasement of politics into theater. “No” treats the spin cycle of electioneering as a given. Like “Lincoln,” which detailed the vote-buying and double-dealing needed to pass the 13th Amendment, it simply accepts that good outcomes can arise from questionable methods — in this case, appealing to voters’ emotions instead of their reason.

The film is set in 1988, giving us a breezy history lesson on the infancy of TV-era politics in South America. We open with Rene (Gael García Bernal), the young creative honcho of a Santiago ad shop, selling some clients on what he’s about to sell them. In a cloud of hazy, high-flown double talk he introduces a commercial for their soft drink, called Free. It’s a cheesy, upbeat ’80s music video — smiling chiquitas, a hair band — with a few product shots thrown in.

When the lights come up, the bottlers are dumbfounded. “Why is there a mime?” one finally asks.

Because Rene knows what sells, that’s why. That’s what has earned him a comfortable lifestyle, complete with a spanking new microwave oven. Still, when dad’s comrades need some advice on marketing, they ask Rene.

After 15 years in power, Chilean dictator Augusto Pinochet has agreed to a referendum vote on whether he should remain in office, in order to give his rule an aura of international legitimacy. His coup and reign was marked by thousands of murders and untold human-rights violations. Still, his government thought it would win in a walk, reckoning that most voters would value middle- and upper-class prosperity over freedom.

The leftists want Rene’s input on their proposed campaign, a dreary account of oppression under Pinochet. “This won’t sell,” he declares. They recruit Rene to fix the campaign. He finds himself matching wits with his boss (Alfredo Castro), who’s consulting for Pinochet. Their sometimes abrasive yet mutually dependent boss-employee relationship echoes the tensions being played out across the nation.

The pro-democracy faction expects the election to be rigged, but hopes to mobilize public opinion through this brief window of free speech. They’re too wonkish and idealistic to grasp Rene’s flash-happy, upbeat, issue-free commercials for regime change. Out of sheer perfectionist professionalism he pushes for the best TV spots possible, alienating most of his harried co-workers, but seizing the nation’s imagination. The spots are hilariously tacky — and as historical clips from Chile’s 1988 campaign show, entirely accurate.

García Bernal underplays the script’s low-key humor to good effect, shifts smoothly to dramatic urgency as needed, and sketches an assured character study of a man gradually engaging in a cause. To his astonishment, Rene buys in to a viewpoint he never felt much connection with.

Director Pablo Larrain gives the film a deliberately retro look, shooting with vintage 1988 home camcorders that give the imagery a cheesy VHS aesthetic. It grows on you. You’ll either get used to the rough, nostalgic look or notice that the smudgy color outlines echo the rainbow symbol Rene uses as the No campaign’s brand symbol. At a time when U.S. politics seems to be aping the noisy, contentious, nonsensical South American model, “No” is a rallying cry to keep the faith, keep smiling and carry on.