Just days after the massacre at a gay nightclub in Orlando, and after a long primary campaign in which Republican candidates often seemed preoccupied with war, terrorism and related fears, Hillary Clinton’s first ad of the general election strikes a gentler and more reassuring tone. It seeks to reintroduce her to voters, ostensibly by highlighting lesser-known aspects of her work on behalf of families and children.

THE MESSAGE Titled “Always,” the minute-long commercial begins with home movie footage of Mrs. Clinton as a toddler, teetering down steps with a grown-up’s help and waving to the camera with a toothy smile. “She would grow up to be one of the most recognizable women in the world,” a male narrator says, over now-familiar pictures of Mrs. Clinton, some alongside her husband. “But less well-known are the causes that have been at the center of her life.” The ad cites her work “helping get disabled kids out of the shadows and into their local schools”; bringing “reform to some of the poorest schools in the nation”; working “with Republicans and Democrats” to enact the Children’s Health Insurance Program, which “today is covering eight million kids”; and, as secretary of state, “working to end the trafficking of women and girls.” Acknowledging, ever so wispily, that “through the years there have been challenges, setbacks,” the ad says one thing has never changed: “Helping children has been a cause of her life, and it always will be.”

THE IMPACT The ad is one of three Mrs. Clinton began running on Thursday in Colorado, Florida, Iowa, Nevada, New Hampshire, North Carolina, Ohio and Virginia. She is following the playbook that President Obama used in 2012, trying to define herself and, with speeches attacking Donald J. Trump, define her opponent too, even before they each officially claim their nominations.

THE TAKEAWAY What is said is important, like the reference to Mrs. Clinton’s bipartisan work in Washington, a strong signal as she goes up against the my-way-or-the-highway Republican candidate, Mr. Trump. But what is shown is what matters most: Photos and video clips serve to humanize Mrs. Clinton as a motherly figure, hugging young people, crouching down with little children; as a protector, standing alongside military officers; and as a hard worker, toting piles of law books, speaking out, or descending from a government plane alone in the middle of the night.