Three campaigns left their positions unclear, and two said they would not join the president on the trail.

Some Republicans in close races have distanced themselves from President Trump’s effort to speed the construction of A.I. data centers, citing concerns about rising electricity bills.

© Caroline Gutman for The New York Times

Even some devoted conservatives know more about Sherrod Brown, the Democratic challenger, than the Republican incumbent, who needs the MAGA base to turn out.

© Maddie McGarvey for The New York Times

A spot from the Senate candidate in Ohio seeks to dismiss the Republican Party’s focus on transgender rights as a distraction from economic issues.

© Sue Ogrocki/Associated Press

Senator Jon Husted, running in a high-stakes race in Ohio, dismissed his political director because of social media activity displaying a “complete lack” of judgment, a spokeswoman said.

© Ruth Fremson/The New York Times