The tone of the ad is celebratory.

“Doug Emhoff,” a narrator says, “would be the first Jewish presidential spouse ever.”

The strategy behind the spot seems to be far more cynical.

A super PAC that appears to have Republican ties is targeting Michigan residents — including those in Detroit-area ZIP codes that are home to many Muslim Americans and Arab Americans — with YouTube advertisements that highlight Vice President Kamala Harris’s support for Israel and, in some cases, the Jewish faith of her husband, Mr. Emhoff.

As the narrator cheerfully notes Mr. Emhoff’s religion, an image of the Israeli flag appears onscreen, a dog whistle conjuring the antisemitic trope of dual loyalty.

“Kamala Harris is a strong leader for these difficult times — and joining Kamala will be her husband and top adviser, Doug Emhoff,” the narrator says, as images cycle across the screen of Mr. Emhoff wearing a yarmulke; visiting Oskar Schindler’s factory; and lighting Hanukkah candles with Ms. Harris. “Kamala Harris and Doug Emhoff: making history, standing up for what’s right, supporting Israel.”

According to the Google Ads Transparency Center, a group called Future Coalition PAC has run six advertisements since Sept. 5, three of which deal explicitly with Mr. Emhoff’s faith. Others focus squarely on Ms. Harris’s support of Israel.