Washington (CNN) Several top Democratic presidential candidates came together ahead of Thursday's presidential debate to support former Rep. Gabby Giffords' political organization and deliver a message on guns: Our children deserve better.

In a powerful video titled "Our Kids Deserve to be Safe at School," eight candidates speak about the need to pass stricter gun laws to prevent mass shootings in schools. The video, the first in a series produced by Giffords' Courage to Fight Gun Violence, will be part of a six-figure digital ad buy targeted toward Houston around this week's third Democratic debate.

While Democratic candidates have some differences on how to combat gun violence, the video stands out because of the candidates' unified message on the issue in the midst of an increasingly contentious primary. Cast against a gray slate and edited to make it appear that the candidates are finishing each other's sentences, the candidates uniformly tout the need for stricter gun laws to protect children.

"We can continue with the corrupt leadership of Donald Trump, who has taken millions from the NRA while opposing gun safety policies, or we can forge a new path and elect a gun-safety president who's willing to stand up to the gun lobby and protect our kids and communities from gun violence," Giffords said in a statement to CNN. "This campaign will give Americans a closer look at just how committed the candidates running against Trump are in the fight to save lives."

Massachusetts Sen. Elizabeth Warren, former Rep. Beto O'Rourke, South Bend, Indiana, Mayor Pete Buttigieg, New Jersey Sen. Cory Booker, California Sen. Kamala Harris, Minnesota Sen. Amy Klobuchar, Vermont Sen. Bernie Sanders and former Vice President Joe Biden all participated in the video. An aide for Giffords' organization tells CNN that all the candidates were invited to participate.

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