North Carolina's 14th district is about to select it's new Congressman - but they're unfortunately stuck with Camden Brady (Will Ferrell
), who's about to win his fourth term simply by running unopposed. All he has to do to win the election is simply appear in front of a judge and sign a few papers. But a recent whistle stop visit to his hometown of Hammond proves to be one disaster after another as he's caught having an affair with a local model named Shana, and then while trying to contact her, accidentally leaves an obscene message on an uber-religious family's answering machine, Cam shoots himself in the foot repeatedly trying to justify his actions. That causes his poll numbers to drop drastically.
The men backing Cam Brady - billionaire industrialist brothers Glenn (John Lithgow
) and Wade (Dan Aykroyd
) Motch - decide that Cam's done and he no longer has the spark he used to have among the voters. They then decide that they need to get somebody new to run against him. That somebody happens to be Marty Huggins (Zach Galifianakis
), the son of former North Carolina senator Raymond Huggins (Brian Cox
), who is a recognized name among conservative voters. Marty runs the Hammond Chamber Of Commerce and the Tourism Bureau, which, not surprisingly enough, Hammond gets no tourists except for maybe a few minor random celebrities that happen to get lost off the interstate. Just as Marty is getting ready to wrap up yet another empty tour bus - which only has a single, obsessed passenger, he gets a phone call from his dad who tells him that the Motch Brothers have tapped him to run against Cam.
Just as Cam is about to sign the papers and make it official that he's NC-14's newest Congressman, Marty shows up at the hearing to make it official that he's going to run against Cam. Cam is shocked because now that means that he has to start a campaign with very little time before the upcoming election.
Elsewhere in China, the Motch Brothers are touring a Chinese factory where they're telling the owners that they can triple the profits that they already make if they eliminate shipping costs. They've got their eyes set on Hammond, North Carolina, and the entire 14th district. Their plan is to buy up large tracts of land where they would construct a Foxconn-esque factory where they paid their workers just slightly above minimum wage. It would create jobs on American soil while growing their already massive fortune, and they start calling their concept "insourcing". The owners wonder what government would cooperate with that, and Glenn assures the owner that they have the one thing they need - a willing candidate. And if you've got that and unlimited money, there's nothing that can stand in your way.
Both Cam's family and Marty's family are seen at their respective houses preparing for the campaign. Cam instructs his kids to put on their headphones while Cam chats with his wife about his recent, very R-rated personal affairs. But Cam's children - who both appear to be middle school aged, it's revealed they are listening to some hardcore gangsta rap on their headphones. Meanwhile, Marty asks his sons and his wife to come forward with any secrets that they may have in case the press were to pick up on it. Both of Marty's sons reveal some incredibly horrifying and disgusting things that they've done when Marty's not around. Even Marty's wife Mitzy admits to some embarrassing atrocities.
Marty makes his first impression on NC-14 when Cam holds a "welcoming luncheon" to introduce Marty as the challenger for NC-14. Marty's first impression is a complete disaster when the only story he has to woo the crowd is a story about his pet pugs barking underneath the sofa. Cam then proceeds to completely humiliate Marty by showing voters what exactly they'll get if they vote for Marty by showing his embarrassing personal life - including the fact that Marty's wife proposed to *HIM* four times before he accepted. Marty also works out at Curves, has Chinese-bred dogs, and is known to crap his pants if somebody tickles him.
Getting into his car and going home, Marty is approached by a man who the Motch Brothers hired to be his new campaign manager - a man named Tim Whatley (Dylan McDermott
). Whatley is there to make Marty not suck. Whatley then proceeds to completely trash the image that Marty had built for himself and do a complete 180. They make over his house, his wife, sons, and replace his pet pugs with a Golden Retriever and a Chocolate Lab. Whatley also tries to whip Marty into a better shape than he's been in.
It's time for the first debate. Marty greets Cam in the theater where the debate is being held. But as they meet, Marty attempts to lay some trash talk on Cam but it quickly backfires on him. Then Marty completely blows away Cam's answer on the first question of the debate, which stuns the audience and scores him huge points in the press. Then Cam commits the unforgivable sin of politicians. Just as he and Marty are going for a photo op with the local babies, they get into a shoving match, and as Cam takes a swing at Marty, Marty ducks and he accidentally hits the baby. Cam's poll numbers drop drastically as a result, and Cam becomes the butt of the jokes of the late night talk show hosts including Chris Matthews (Chris Matthews
) and Bill Maher (Bill Maher
The next day at his campaign headquarters, Cam is going over some new campaign commercials. The first is a commercial that completely ignores all the things that Cam has done as a politician while highlighting his affair with gorgeous model / yoga instructor Shana, but while that commercial was a hit with men, it scored terribly low numbers with women. The second commercial paints Marty Huggins as a member of the Taliban or Al-Qaeda, suggesting that if Marty has a mustache and Saddam Hussein has a mustache, they must be related. Neither of these commercials send good messages to the voters, and Cam's campaign manager Mitch (Jason Sudeikis
) strongly recommend against them.
At the next debate - after shooting himself in the foot with the al Qaeda / Taliban comparison, the topic of religion is brought up. Marty accuses Cam of not having been to church in several months - with NC-14 being an incredibly religious district. Cam proves this by being unable to cite the traditional Catholic Lord's Prayer. Cam eggs on Marty that if he wants a holy war, he's got one. The two are then seen at several congregations of various faiths - Marty attends mass at a Catholic Church and a Jewish Temple, while Cam sings in a gospel choir at a Southern Baptist church and attends a Snake Handler ceremony. While at the Snake Handler mass, he's bit by a rather venomous rattle snake. The venom causes his arm to swell up like a balloon and gives him some mild hallucinations. He then freaks out and destroys the living room of the same family that he left an obscene voice mail message on earlier. Just as he's being wheeled out of the hospital, Cam's snake bit shockingly causes his numbers to rise in the polls.
The next night, Cam stops by Marty's house for a friendly chat. He decides that this campaign can work if they can put aside their differences and become friends. Marty thinks that's a very noble way to go about doing things, but isn't sure that he's ready to trust Cam. He then offers Cam some small batch bourbon, which Cam then proceeds to drink quite heavily. On his way home, Cam's stopped for a DUI. He takes the police cruiser out for a joy ride and is subsequently arrested. At the jail the next morning he's hounded by the press and is still too drunk from the previous night to drive.
Things get real in the third debate. Marty has obtained a copy of a coloring book that Cam wrote as an elementary school student called "Rainbowland". Rainbowland features writing that Marty tells the audience has socialist undertones, which gets the crowd incredibly riled up. Cam tries to assure the crowd that he was 8 years old at the time he wrote that and that it means absolutely nothing. A near riot begins to break out and Cam tries to discover Marty's tickling pant-crapping secret if it's true or not. Just as Cam heads for Marty and begins to throw a punch, Marty ducks and Cam hits the dog from "The Artist". That once again gets him to be the butt of the jokes of the late night community. Also, not surprisingly, the e-book version of "Rainbowland" has become the most downloaded title on Amazon.
Marty is watching the aftermath of the events unfold at his house. His wife Mitzy is yelling at him about how Marty's never home. They then decide to have a family night with the pugs - and everyone is seen stuffing their faces with all kinds of junk food. Tim Whatley shows up wasted and begins yelling at Marty that he needs to stop screwing around and take this campaign more seriously.
Back at campaign headquarters, Cam Jr. tells his father that he's considering running for election for class president, and his father gives him advice on how to smear his opponents. Cam's campaign manager then presents to him a shocking new campaign commercial from Marty Huggins. It's footage of Marty having small talk with Cam's son, trying to get sympathy from the audience as to how Cam's not a good father. Cam, furious, now retaliates by attempting to woo Marty's wife Mitzy into having an illicit affair with him. He then films it using his smart phone camera and uses that as his next campaign commercial. His campaign manager is horrified that he would try such a thing.
Cam proceeds to freak out and fires his campaign manager Mitch as a result. He will do anything to get this commercial on the air. He then proceeds to look around his staff for anybody who would have the balls to put this commercial on the air. He finally succeeds, and the controversial commercial is aired. During a live on air interview from his house, Piers Morgan criticizes the commercial live on air in front of Cam, while explaining that the video itself attracts nearly 65,000,000 viewers on YouTube. The interview proves to be a huge disaster as Cam can't directly answer Piers' burning questions and at one point begins endorsing Marty Huggins for Congress over his own campaign.
Marty gets in a subsequent argument with his wife, causing her to take the children to her mother's. Cam's wife, disgusted by the video and the fact that he's way behind in the polls, also leaves him. During a photo op on a hunting range, Marty takes his shotgun and shoots Cam in the leg, causing Marty's poll numbers to rise drastically.
Now celebrating, just as Marty's latest stunt causes his poll numbers to skyrocket, Glenn and Wade Motch decide they've got this in the bag. They're celebrating at the mansion with Marty and Raymond, and then proceed to tell Marty about the plan they have for NC-14 which is basically opening a large sweatshop on US soil which would triple the profits they make and eliminate shipping costs. Marty is horrified to hear this and considers backing out of the campaign completely as he doesn't want to do anything to hurt his hometown. He doesn't want to be known as the guy who sold NC-14 to the Chinese. Frustrated, Glenn and Wade Motch decide their next course of action and that's to finance someone who's willing to cooperate. They then see that they've had the right man all along this entire time: Cam Brady, who's given an electrified concert where he makes his reentrance to the campagin - complete with Bachmann Turner Overdrive themselves playing a pyrotechnic filled rendition of "Taking Care Of Business" - his campaign theme song. At Cam Brady's re entrance to the top of the campaign, he's greeted by his wife Rose, who's only there because the Motch Brothers paid her to make an appearance at the event.
It's election day and this race is among the most highly watched campaigns in the entire country because it was so volatile. Marty rounds up what's left of his campaign staff and has him put on a last minute commercial. There, Marty explains the truth behind his campaign - that he was financed by the Motch Brothers. That he wasn't being faithful to his wife or his sons. He then tells people to reveal the truth about themselves. This causes a bizarre chain of events to unfold around the entire district. Later that night, the campaign numbers are finally tallied. Marty and Mitzy reconcile their differences after Mitzy is impressed with Marty's last campaign ad. Cam has won by a very sizable margin of nearly 10,000 votes. It's then revealed that the Motch Brothers own the voting machines that were being used in the election. Cam congratulates Marty on a job well done and tells him that he's got a natural knack for campaigning.
But then Marty explains to Cam that he just doesn't get it. Being a Congressman is not a job you can just phone in, it's about taking action. Marty tells Cam that he voted for him in elementary school to take down the jaggedy jungle gym that was causing so many student injuries. Cam and Marty both reveal their injuries that they sustained on the contraption. Cam is horrified to see the extent of Marty's scars, and as he takes the podium, he finally reveals the truth about himself that he's not a very good Congressman because he took money from the Motch brothers and phoned in everything he was supposed to vote on, and hands the office over to Marty and becomes Marty's chief of staff. During the concession speech, Cam points out that the Motch Brothers are behind his decision to step down, and that they're responsible for ruining the district he's been proud to represent the last 15 years. The Motch Brothers - who were at the event, quickly make their exit. The next day the Motch Brothers are eying Scott Talley's district, after he's caught in yet another scandal and decide to run someone against him, saying that Talley no longer has the spark among voters that he used to. But unfortunately they get subpoenaed to appear before the US Congressional Committee On Campaign Finance Reform - now headed by Congressman Marty Huggins.
The movie ends with a post credits scene that shows the Motch Borthers appearing in a hearing before Congress where Marty is nailing them about buying districts to increase their profits. They explain that because of a recent Supreme Court ruling, that's now allowed. But then Marty comes back and exposes Tim Whatley as being involved in criminal fraudulent activity, and that because the Motches are backing a criminal, that makes them criminals by association and has them arrested and detained.