The episode is set during a party thrown by Shiv (Sarah Snook) and Tom (Matthew Macfadyen) at their apartment for major business and political figures the night before the United States presidential election, and sees the continuation of the past few episodes' storyline, in which Kendall (Jeremy Strong) and Roman (Kieran Culkin) attempt to sabotage the GoJo deal they have been negotiating with Lukas Matsson (Alexander Skarsgård).
One day before the presidential election, Shiv and Tom prepare to host the Roys' traditional pre-election party for business and political insiders at their apartment; Matsson declines the invitation.
However, Kendall and Roman get Shiv's permission to invite Nate to the party, hoping to use his bipartisan connections with lawmakers to amass a regulatory push against GoJo's acquisition of Waystar.
Shiv takes Matsson to network with the guests in order to secure support for the acquisition; he implies to Nate that Tom will be fired from his leadership of ATN once the deal goes through.
Roman finds Gerri and apologizes for firing her, passing it off as an overreaction, but she refuses to return to Waystar, having already negotiated a hefty severance agreement that includes no negative publicity around her exit.
The website's critical consensus states, "Presenting scenes from a marriage that culminate in the ultimate blowup, "Tailgate Party" dishes out plenty of hors d'oeuvres with the Roy clan's backstabbing, but the main course is Sarah Snook and Matthew Macfadyen's explosive performances.
"[7] Pamela Paul of The New York Times called the episode "one of the best in the four-season series", and felt its examination of Shiv and Tom's marriage brought forth a "depth and poignancy often pointedly absent from the show’s usual orchestrations of insult.
[9] Scott Tobias of Vulture gave the episode of 5 out of 5 stars, writing that Snook and Macfadyen "deliver the bullet points of this collapsing marriage with full feeling" during the "extraordinary" argument scene between Shiv and Tom.
[12] While praising the "spectacularly played" Shiv-Tom confrontation, Alan Sepinwall of Rolling Stone found the episode's other subplots less compelling by comparison, writing that "it all feels very much in the shadow of what’s happening with the party’s two hosts.
"[14] Nick Clark of the Evening Standard, meanwhile, found a "scattergun" quality to Shiv and Tom's progression from "the heights of rekindled romance (...) to a blazing row" within the span of a single episode.
He suggested that the series was "in a holding pattern" since the season's midpoint, "seeding storylines, foreshadowing big events, teasing emotional turmoil, but keeping its powder dry.