“Mike DeWine has promised me he will protect those with pre-existing conditions,” Mr. Kasich says. “Mike knows the success we’ve had in Ohio by not leaving anyone behind. DeWine will work to make health care available and affordable.”

Joshua Eck, a spokesman for the DeWine campaign, said the ad was currently running on digital platforms only. He said he was not aware of plans to put it on television.

Tester gets personal

Senator Jon Tester of Montana is breaking out his own campaign closer: an old meat grinder with a bloody history.

Throughout his career, Mr. Tester — one of several Democrats hoping to hang on in states the president won easily — has spoken often of the meat grinder, which cost him three fingers in an accident when he was a child.

But its re-emergence in an ad this week is instructive. Mr. Tester is staking his race against Matt Rosendale, a Republican Trump acolyte and the state auditor, on two things: his homespun brand as a Montana lifer and an emphasis on local issues like the state’s health care system.

Mr. Rosendale, by contrast, has sought to nationalize the race, tying himself to the president in a state Mr. Trump won by 20.

The ad seems aimed at accomplishing both of Mr. Tester’s goals.

“I was 9-years-old when I lost my fingers in this meat grinder,” he says in the ad. “My parents paid for the hospital because our health care didn’t cover anything.”