Days before the US midterm elections, an attack advertisement for the Ohio gubernatorial race has kicked up a storm nationwide.The advertisement, produced by Republican candidate Vivek Ramaswamy’s campaign, features Donna Arthur, the estranged mother of his Democratic opponent, Amy Acton. Arthur calls her daughter “a liar” in the ad and suggests she has mental health problems.But the ad omits the disturbing reason for the estrangement: Arthur’s second husband was charged with raping Acton when she was a child. Acton, then 12, and her brother were subsequently removed from Arthur’s custody.Vivek Ramaswamy is not fit to lead. Watch our new ad. https://t.co/EhWNMdFjjH— Dr. Amy Acton (@amyactonoh) October 20, 2026The advertisement has drawn criticism from both Republicans and Democrats, even though US President Donald Trump and Vice President J D Vance have publicly backed Ramaswamy. Trump called the ad “very powerful” in a Truth Social post, adding, “Who wouldn’t use such an Ad?” Vance, on the other hand, praised Ramaswamy’s”audacity to run a TV commercial which calls it out like it is.” He later said hat voters should “focus on the substance”.The episode raises the question: How far can political campaigns go in attacking their opponents?Negative campaigning and ‘dirty tricks’The Wesleyan Media Project, a non-partisan group that tracks political advertising in US elections, identifies positive advertising as ads focused primarily on promoting a candidate. Negative advertising, by contrast, may comprise attack ads, which focus primarily on attacking another candidate, and contrast ads, which include both a promotional and attack message.Negative campaigning, however, is not necessarily the same as “dirty tricks”. In their 2019 book Dirty Tricks in the Digital Age, political scientists Elaine Kamarck and Darrell West distinguish negative campaigning, which involves attacks grounded in actual events, from “dirty tricks”, which involve fabricated allegations, deception or interference with the electoral process. An attack can be offensive, or even misleading, without being entirely fabricated.Also in Explained | Why a labour rights activist’s detention has put a broad China law under scrutinyAccording to Dictionary.com, the term “dirty tricks” was originally associated with the US Central Intelligence Agency, whose clandestine operations against foreign adversaries earned its planning directorate the name “Department of Dirty Tricks”.Story continues below this adThe term is also popularly associated with the Watergate scandal, which began in 1972 when five men broke into the Democratic National Committee headquarters in Washington. The subsequent investigation uncovered political sabotage linked to President Richard Nixon’s administration, ultimately leading to his resignation in August 1974.Yet negative campaigning need not involve deception. In his 2006 book, In Defense of Negativity: Attack Ads in Presidential Campaigns, political science professor John G Geer argues that criticism of a candidate can serve voters, even when it is uncivil.“The real issue should be whether or not candidates present the information in campaigns that is useful to voters. The tone of that information should be a secondary issue, at best,” he wrote.Political advertising in the USThe concept of political mudslinging dates back to the formation of the US. Long before television existed, presidential hopefuls Thomas Jefferson and John Adams traded scathing attacks through partisan newspapers during the 1800 election. Jefferson’s supporters called Adams a monarchist — a scandalous claim in the early years of the US — while Adams’ supporters called Jefferson an atheist. In his book, Geer wrote that Jefferson was accused of supporting “murder, robbery, rape, adultery, and incest.”Story continues below this adIn 1884, Grover Cleveland’s Republican opponents seized on allegations that he had fathered a child outside marriage, popularising the taunt “Ma, Ma, where’s my Pa?”With the advent of television, political attacks were no longer confined to the printed word. One of the most widely cited examples is the infamous 1964 Daisy ad, which aired only once, on September 7, but became one of the most influential political advertisements in American history.The television ad, officially titled “Peace, Little Girl”, features a child plucking petals off a daisy and counting them. Another voice counts down to zero, followed by a nuclear blast after which Lyndon B Johnson is heard saying: “These are the stakes—to make a world in which all of God’s children can live or to go into the dark. We must either love each other or we must die.” A narrator then urges viewers to vote for Johnson, warning that the stakes are too high to stay home.Johnson’s Republican opponent, Barry Goldwater, who was implicitly targeted, condemned the advertisement for suggesting that his election could lead to nuclear war.Story continues below this adMore than two decades later, the infamous 1988 Willie Horton ad directly attacked a candidate’s record. It was also widely condemned as racist for playing on fears and stereotypes about Black men and crime.During a presidential campaign in which crime became a major issue, a group supporting Republican presidential candidate George H W Bush released the ad, linking Willie Horton, a convicted murderer who committed further violent crimes while on furlough from prison, with Michael Dukakis, Bush’s Democratic rival.The ad meant to show Dukakis as being “soft on crime”, linking his opposition to the death penalty to a Massachusetts prison furlough programme that operated during his governorship and permitted prisoners serving life sentences to leave prison temporarily. “Horton received 10 weekend passes from prison. Horton fled, kidnapped a young couple, stabbing the man, and repeatedly raping his girlfriend,” the ad says.The advent of social media also gave an unprecedented reach to the kind of fabricated allegations associated with “dirty tricks”. The 2016 presidential campaign notably witnessed “Pizzagate”, in which a conspiracy theory spread across social media alleging that Democratic candidate Hillary Clinton’s campaign manager’s emails had coded references to a child sex ring run by high-ranking members of the party. The fabricated claims centred on a Washington DC pizzeria.Story continues below this adFollowing the 2020 election, Donald Trump’s campaign released television advertisements alleging widespread electoral fraud, including one titled STOP THE STEAL! The claims were false. In 2024, baseless allegations that Haitian immigrants in Springfield, Ohio, were abducting and eating neighbourhood pets circulated widely online and were even featured on billboards commissioned by the Arizona Republican Party.Also Read | Ilhan Omar: Why the US democrat is being targeted by Donald TrumpBy 2026, artificial intelligence (AI) has added another dimension to political advertising, allowing campaigns to create everything from minor visual enhancements to convincing but fabricated depictions of candidates. Citing research by the Wesleyan Media Project, The New York Times reported that over $137 million was spent promoting over 220 advertisements featuring AI-generated content during the US midterm campaigns. Nearly 70% of these advertisements did not disclose the use of AI. The technology has also made elaborate campaign videos considerably cheaper, while making it harder to distinguish genuine footage from fabricated material.Do negative political ads work?A 1999 meta-analysis by political scientists Richard Lau, Lee Sigelman and colleagues found little evidence that negative advertisements were more effective than positive ones, or that they significantly discouraged political participation. A 1990 study by Gina Garramone and colleagues, meanwhile, suggested that negative advertisements could sharpen voters’ perceptions of differences between candidates without necessarily affecting their likelihood of voting.However, a 2016 study by Jared Barton, Marco Castillo and Ragan Petrie found that negative campaign letters increased turnout among supporters compared with positive letters in two local elections. More recently, a 2022 study by Yingying Chen and Luping Wang found that hostile exchanges in the comments on a misleading Trump campaign video on YouTube tended to continue, showing how such advertisements could fuel hostility online.Story continues below this adA candidate’s use of negative campaigning also need not cost them support, even when voters disapprove of their tactics. In a post-election survey in November 2024, the Pew Research Center found that 68% of Trump voters considered the presidential campaign too negative. Yet 82% said they had voted primarily in support of Donald Trump, rather than against Kamala Harris.Voters have overlooked controversial conduct before. During his successful 1983 campaign for Louisiana governor, Edwin Edwards famously declared that he could lose only if he was caught in bed with “either a dead girl or a live boy”.In Ohio, recent opinion polls show Acton ahead of Ramaswamy. The RealClearPolling average puts Acton at 48.5% and Ramaswamy at 44.9%, while an October 15–19 Fox News poll found a narrower 50–48% margin. On October 24, the Kalshi betting market priced an Acton victory at approximately 82%, against 19% for Ramaswamy.In Ohio, however, the negative strategem appears to have backfired on Ramaswamy. Though Acton’s prospects had already been improving, Ramaswamy’s odds nosedived further following the airing of the advertisement — which has attracted criticism even from Republicans — according to the popular betting site Kalshi. As per Kalshi, Acton’s chances increased from 68% on October 14 to 76% on October 20, following the controversy, and climbed further to 81% by October 22.