Former US President Barack Obama took direct aim at Indian-American Republican gubernatorial candidate Vivek Ramaswamy on Saturday at a rally in Cleveland, Ohio, calling him 'thirsty' for attention and accusing him of crossing ethical lines with a campaign advertisement featuring his Democratic rival's estranged mother.

Obama's Attack in Cleveland

Speaking at the Cleveland Public Auditorium during his first rally of the midterm campaign season, Obama drew knowing laughter from the crowd with a sharp characterisation of Ramaswamy. 'We all know that guy — who is, like, thirsty,' Obama said. 'Just wants to get attention no matter what, willing to do anything. And in recent days we've seen there is no line he won't cross.'

Obama added: 'I don't know what's happened where the standards of behavior have gotten so low that somebody can run an ad like that.' He spent much of his 35-minute address boosting Democrat Amy Acton, Ramaswamy's rival in the Ohio governor's race, and former Senator Sherrod Brown, who is seeking to reclaim his old seat. Obama also devoted significant time to attacking President Donald Trump.

The Controversial Ad at the Centre of the Storm

The backlash stems from a Ramaswamy campaign advertisement in which Donna Arthur — Acton's estranged mother — calls her daughter a 'liar.' Acton has stated she has neither seen nor spoken to Arthur in nearly 50 years and was removed from her custody in 1978 after her then-stepfather was charged with rape. Acton, 60, a physician who led Ohio's Covid-19 response as health director, addressed the controversy directly at the rally. 'My opponent has chosen to exploit, intentionally, my childhood to save his struggling campaign, but it's not going to work,' she said.

Following the growing controversy, the Ramaswamy campaign reportedly switched to a 30-second version of the ad. According to a person close to the campaign cited by NBC News, the shorter cut removes the mother's disputed claim that Acton never lived in a tent as a child.

Republican Reaction: A Party Divided

The ad has exposed a visible split within the Republican Party in Ohio. Governor Mike DeWine, who has endorsed Ramaswamy, called the ad 'deeply, deeply troubling.' Vice President JD Vance, by contrast, told fellow Republicans to 'stop whining.' President Trump, who has endorsed Ramaswamy, 41, a biotech entrepreneur born and raised in Ohio, described the ad as 'very powerful.'

The Ramaswamy campaign pushed back through spokesperson Connie Luck, saying: 'Ohioans can't afford a liberal governor who shows up for Obama but never shows up for them.'

Race Shifts Toward Democrats as Money Flows to Acton

The political fallout has been swift. The Cook Political Report moved the Ohio governor's race from toss-up to Lean Democratic on Friday, directly citing the controversy around the ad. Sabato's Crystal Ball similarly rates the race as Lean Democratic.

The backlash has also translated into fundraising momentum for Acton. MK Pritzker, wife of Illinois Governor JB Pritzker, donated $500,000 to Acton's campaign, according to reports. A victory for Acton on 3 November would make her Ohio's first Democratic governor in 20 years. Trump is scheduled to return to Ohio next week for an event in Chillicothe.