"Let's break down barriers, so we can all rise together, do all the good we can, in all the ways we can, for all the people we can," the ad says. "Let's protect each other. Let's stand together."
Music for the ad was written and performed by soul singer Andra Day, who also performed at a Clinton fundraising concert in New York earlier this year.
It will air in Philadelphia, Pittsburgh, Baltimore, and Hartford media markets.
The message of unity comes at a time when Clinton has pivoted away from attacking Sen. Bernie Sanders of Vermont after defeating him soundly in last week's New York primary. Although Sanders has vowed to stay in the race, upcoming primaries on Tuesday could make the task all the more difficult if he is unable to secure several much-needed victories and close the yawning gap in delegates that Clinton has racked up.
And although the ad does not mention Republican presidential candidate Donald Trump, as Clinton's previous ads have, the message of "love and kindness" is one that Clinton has often deployed on the campaign trail in response to Trump's rhetoric.