"This is who I am," DeMaio told the Journal. "It's something that's important to me. I want to embrace equality, and feel like the party should, too."
He told the newspaper that he had wanted to feature Hale in ads during his unsuccessful run for San Diego mayor in 2012, but his then-campaign advisers discouraged it. He's since hired new talent, he said.
DeMaio is considered the frontrunner for the Republican nod after receiving endorsements from House Republican leaders. The seat is considered a toss-up by the Cook Political Report.
The ad was posted to YouTube Monday.