Stewart Superior Corp.

Darron Cummings / AP Photo

INDIANAPOLIS (AP) — In the high-stakes battle for a pivotal Indiana Senate seat, Democrat Joe Donnelly has repeatedly attacked his opponent, multimillionaire auto-parts magnate Mike Braun, for importing the products he sells from China.

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.