The film premiered as an "Official Selection" at the 2005 Cannes Film Festival, before being released in Hong Kong on 20 October 2005, with a Category III rating. A sequel to the film, Election 2 (also known as Triad Election in the United States), concluded the film, and was released in 2006.
The movie begins as the two-year term expires, and all the elders of the Wo Luen Shing are in the process of electing a new chairman, with some last-minute "campaigning" from both Lok and Big D just a few days prior to the election. Lok is calm, patient and even-tempered, while Big D, who attempts to buy the election, is boisterous, impatient and quick-tempered. After bitter arguments from supporters of both candidates in the likes of Uncle Cocky and Uncle Monk, Lok is elected as the new chairman. However, Big D is dismayed by the result and proceeds to punish two men responsible for his loss by kidnapping them and rolling them down a hill in boxes, prompting ex-chairman Whistle to ask his lieutenant Four-Eye to hide the dragon head baton, which is a symbol of power for the leader.
In an attempt to keep the peace and prevent infighting, the police, headed by Chief Superintendent Hui, arrest the key Triad figures, including Uncle Teng, Big D, Uncle Cocky, Uncle Monk and the newly elected chairman Lok of the Wo Luen Shing. However, during a negotiation attempt in a holding cell, Big D, in a fit of rage, threatens to break with the Triad and form his own society. The culture of the Triad emphasises brotherhood and unity; such a revolt would not be accepted by the Triad, and would lead to heavy violence. Both the heads of the Triad and the police want to avoid turf warfare.
Meanwhile, a pursuit of the baton ensues in which Kun (Blacky's henchman), who is recovering the baton for Big D catches up with Big Head (Tally's henchman), who holds the baton and is recovering it for Lok. During the confrontation, Kun severely beats Big Head with a giant log in order for him to hand out the baton when Kun's boss informs him that the plan has changed and that Kun is to recover the baton for Lok. The leaders are eventually released on bail and after hours of pursuit between Kun, Jimmy, and Jet on route, Lok eventually receives the baton from Jimmy thus making his election official.
Lok proposes a truce, which Big D accepts, on the terms that they will be partners and Big D will be the next chairman when Lok's term expires. Initially, this is a successful partnership; together they expand the Triad's turf. In contrast to his earlier behaviour, Big D becomes loyal to Lok, whom he now considers a good friend.
In the final scene, Lok and Big D are fishing on a sunny afternoon, accompanied by Lok's young son, Denny, and Big D's wife. While momentarily alone with Lok, Big D proposes that they share the power of chairman; it is not an uncommon practice to have more than one chairman. Lok agrees to support Big D. However, seconds later Lok attacks Big D from behind, using a small boulder to repeatedly smash in his head. Denny and Big D's wife return in time to see this. Lok orders his son to wait in the car, and proceeds to finish murdering Big D. He then runs after Big D's wife, attacking her with a shovel and then crushing her throat with a heavy branch. He buries both bodies, washes his hands in the water and goes to the car, where his visibly shaken son is waiting.
At the end of its box-office run in Hong Kong, Election grossed about HK$15.59 million, which is considered to be quite high for a film that received a Category III rating (18+ restriction) in Hong Kong.
The A.V. Club's Ignatiy Vishnevetsky writes, "[Johnnie] To’s saga makes plain that self-interest, far more than traditional ideas about honor, defines contemporary crooks. While that’s hardly an astonishing revelation, the writer-director deftly generates suspense (as well as sly comedy) from a mood of all-consuming untrustworthiness. [...] Thrilling and amusing in equally dark measure, it’s an incisive portrait of a dysfunctional family-style organization struggling to update its sordid operation in an age of unchecked capitalist greed."
Election was sold to more than 21 territories, including Optimum Releasing for the United Kingdom, ARP Sélection for France and Hopscotch Films for Australia, after screening at the 2005 Cannes Film Festival in competition. Tartan Films has acquired all United States rights to this movie as of May 2006.
The movie is notable in being nominated for 14 Golden Horse Awards in Hong Kong cinema. The film was named Best Film of 2005 in the Hong Kong Film Critics Society Awards, with To also clinching Best Director honours for the movie.