Arkansas Republican Rep. Tom Cotton’s Political Action Committee (PAC), the Republican Majority Fund, is airing a new attack ad about Democratic presidential frontrunner Joe Biden in Ohio five days before the state’s primary on Tuesday.

The ad goes after the former vice president for being “weak on China,” where his scandal-ridden son, Hunter Biden, has conducted questionable business while Joe Biden voted to give the east Asian giant special trade status as a Delaware senator.

The ad begins by condemning China’s record on human rights and aggressive history of cyberwarfare.

“They run concentration camps. They forced the abortions of millions of babies. They brutally crack down on protesters. They hack America’s networks. They have stolen millions of our jobs,” a narrator says to dark images depicting Chinese abuses. “China is the greatest threat to our national security and our values. Career politician Joe Biden is weak on China.”

The new ad is part of a five-figure buy that will air in regions of the state hardest hit by manufacturing job losses. The ad will also play digitally in swing states across the country as part of Cotton’s effort to elect conservative veterans and aid in President Donald Trump’s re-election this fall.

“Throughout his career, almost every time he got the chance, Joe Biden took China’s side and American workers are still suffering for it,” Cotton told The Federalist. “Last year, Joe Biden claimed that China is ‘not competition for us’ and last month, he opposed President Trump’s travel ban on China as ‘xenophobic.’ Whatever the issue, Biden can be relied on to take China’s side.”

The attack ad targeting Biden on China in regions hollowed out by trade deals comes on the heels of Biden becoming the presumptive nominee after another series of major wins on Tuesday over his last standing rival in the race, Vermont Sen. Bernie Sanders. Hawaii Rep. Tulsi Gabbard remains in the race but has yet to capture a single state contest.

Biden’s wide victories in Mississippi, Idaho, Missouri, and Michigan have narrowed the path for Sanders to reach the 1,991 delegates required to clinch the nomination. Sanders’ loss in Michigan spells more trouble for the Vermont senator, who must prove he can capture critical Rust Belt states against Trump this fall.

Cotton’s Biden attack ad airing in Ohio might play to Sanders’s benefit in the state’s primaries next week as Sanders has targeted Biden on trade. It looks mathematically unlikely at this point that Sanders can overcome the delegate gap over Biden to win the nomination in Milwaukee. Biden currently leads Sanders with 838 delegates to Sanders’s 691.