It's a potent issue for the incumbent senator in a manufacturing powerhouse state where "made in America" is an identity - not just a slogan - and railing against foreign outsourcing helped President Donald Trump rack up a win by 19 percentage points.
Yet for Donnelly, whose neck-and-neck race with Braun could help determine which party controls the Senate, it ignores one inconvenient detail. Stewart Superior Corp., a family business that he owned stock in, has also received repeated shipments of goods from China for much of this decade, records reviewed by The Associated Press show.
That makes Donnelly susceptible to charges of hypocrisy while undercutting one of his main attacks on Braun before an election in which working-class support will be crucial. It's also likely to ratchet up a GOP onslaught that was already intensifying after Donnelly cast a "no" vote against Trump's second Supreme Court pick, Brett Kavanaugh.
Donnelly's campaign did not directly address the shipments, but noted that the senator sold his stock in the company last year and donated $17,410 in proceeds to charity.
Spokesman Will Baskin-Gerwitz also attacked Braun, who he said "continues to lie repeatedly about the fact that he profits every single day from Chinese labor at the expense of Hoosier workers."
Stewart Superior's imports from China, which have been referenced in attack ads, are minuscule when compared to the goods Braun regularly receives from the country.
Between 2011 and 2017, a time when Donnelly owned as much as $50,000 in company stock, Stewart Superior received more than 120,000 pounds of Chinese materials, spread out across more than 20 shipments, according to the website Panjiva, which tracks international trade. He collected dividend payments in 2016 worth between $15,001 and $50,000, according to Senate financial disclosures.
In comparison, Braun's auto-parts empire, which employs 850 workers at 70 locations across the U.S., obtains Chinese goods through intermediary companies that have imported thousands of shipments in recent years. His stock income from the business was $4.5 million last year, records show.
It's not the first time Donnelly has drawn unwanted attention for his ties to his family's company, which is operated by his brother. The longtime outsourcing opponent, who is one of a handful of red-state Democrats running for re-election, faced withering criticism last year after news reports revealed the business operated a factory in Mexico.
Republicans labeled him "Mexico Joe," ran ads with him wearing a sombrero and even sent a Mariachi band to play outside his campaign kickoff.
But after Braun unexpectedly beat two sitting congressmen in the GOP primary, Democrats saw an opportunity to flip the script by focusing on his business practices.
They wave Chinese flags outside Braun campaign events and, in a recent prank, delivered a box of the flags to his campaign headquarters along with a note signed in Chinese.
In an ad, Donnelly stands next to a pickup brimming with boxes of Braun's auto parts while declaring that he "voted against every bad trade deal."
"Mike Braun has used those same trade deals to outsource Hoosier jobs to China," he says after tapping his finger on a label that says "made in China."
Experts say it's not just normal for businesses and manufacturers to rely on supply chains that include at least some foreign goods - they say it's unusual when companies don't. And some longtime political observers say they hear troubling echoes from Indiana's history of nativism and nationalism.
"Xenophobia is certainly in the campaign," said former Lt. Gov. John Mutz, a well-respected Republican and elder statesman who blames "both sides."
Mutz would know. As lieutenant governor, he helped persuade Subaru to build a plant in Indiana that has since become a major employer. When Mutz ran for governor in 1988, though, he was subject to ruthless attack ads by Democrat Evan Bayh that focused on the fact that the automaker was Japanese. Mutz lost and ever since, he's held up the campaign as a cautionary tale of nativist forces that can seep into politics.
"There's an undercurrent that is still present," he added. "It's unfortunate."
Braun's campaign did not respond to a request for comment on the criticism.
But Baskin-Gerwitz, Donnelly's spokesman, dismissed it outright and said the senator would "never apologize for sticking up for American workers."
"Mike Braun has made (millions) a year from his Chinese auto parts while Indiana factories making the same parts went out of business," Baskin-Gerwitz said. "Joe is going to make sure voters know that, and if that offends some people, then it's time they put Indiana and Indiana workers first."
Robert Dion, a political science professor at the University of Evansville, said it's not uncommon for candidates in a close race to walk a thin line between "light-hearted campaigning and pandering to our baser instincts."
"There is a bit of an unsavory element to this kind of campaigning," he said. "Unfortunately when there is a close election, we tend to see these kinds of things ratchet up. Everything gets turned up to 11."
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