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By Sherri Williams

Maria Hamilton’s voice was raspy and worn as she talked about the night her son Dontre’ Hamilton was fatally shot 14 times by police in Milwaukee, Wis. in 2015. Through a brutal cough she spoke about why she became an advocate for police reform and a campaign supporter for Hillary Clinton.

“Why I fight? I was one of the walking dead people like you before it hit my door,” she said of police brutality in September on a campaign stop in a packed auditorium at North Carolina A&T University in Greensboro, N.C. “I have walking pneumonia but I wouldn't have missed this.”

Hamilton and other Mothers of the Movement, black mothers who lost their children to police brutality or gun violence, have logged hundreds of miles traveling across the country, visiting battleground states – sometimes twice – urging people to use their ballots as a tool to fight police brutality.

U.S. Democratic presidential nominee Hillary Clinton listens to Geneva Reed-Veal, a member of "Mothers of the Movement," a group of women who have lost their children in a series of police shootings which galvanized the "Black Lives Matter" movement, during a Sunday service at Union Baptist Church , North Carolina, U.S., October 23, 2016.CARLOS BARRIA / Reuters

For them the 2016 presidential election is a matter of life and death. They don’t want others to lose their children to police brutality and gun violence.

They first showed their collective endorsement for Clinton in July at the Democratic National Convention in Philadelphia. That night Maria Hamilton, Lucia McBath, Gwen Carr, Geneva Reed-Veal, Sybrina Fulton, Annette Nance-Holt, Lezley McSpadden, Wanda Johnson and Cleopatra Pendleton-Cowley stood on stage together in solidarity with one another and in support of Clinton.

Since then some of them made more than 20 campaign stops, said Denise Horn, director of black media for the Hillary Clinton campaign, and once they arrived they often visited multiple cities.

The mothers are campaigning for Clinton right up to Election Day in this tight and polarizing presidential race. On Tuesday night they’ll be with Clinton at the Jacob K. Javits Convention Center in Manhattan, Horn said.

Election Day will mark the official end of months of trekking across the nation on the campaign trail retelling the painful stories of their children’s deaths, living their heartache openly, inviting the public to see their vulnerability and grief as well as their passion for social justice and policy reform.

RELATED: 'Mothers of the Movement' Back Clinton in Convention Speeches

They spent time away from their families. They rushed to several campaign events in a single day. They kept the stories of their deceased children front and center long after their names fell out of news cycles and social media streams.

“I’m turning my mourning into a movement and my sorrow into a strategy.” — Gwen Carr

“We’re the moms that fly all across this country. We got lovers and children and mothers and grandmothers in our lives too,” Hamilton said. “But when you’re passionate about getting it right you do this…We didn’t ask to be acknowledged. We’re not happy to be here. But we’re determined to build a better life and Hillary has given us that platform.”

Lucia McBath, whose son Jordan Davis was fatally shot in 2012 in Florida by a vigilante who was disturbed by the loud music coming from Davis' car, spent the weekend before Election Day on the campaign trail in Nevada. Sybrina Fulton spent her Saturday in Florida where she introduced the Secretary at a "Get Out the Vote" rally in Pembroke Pines.

Their commitment to the campaign is strong and consistent, Horn said. “Every day they’re doing something in some capacity for the campaign.”

Outside of the scheduled campaign stops the Mothers of the Movement often connected with other people who lost their relatives to police and gun violence while they were on the campaign trail, Horn said.

"We didn’t ask to be acknowledged. We’re not happy to be here. But we’re determined to build a better life and Hillary has given us that platform.” — Maria Hamilton

As the mothers traveled cross the country they were also constantly reminded of the ways in which black people's interactions with the police can become deadly. They were in Greensboro, N.C. in September campaigning for Clinton the day before Keith Lamont Scott was fatally shot by a police officer in Charlotte. Scott's death spurred almost a week of mass protests in the city.

Gwen Carr, the mother of Eric Garner who died in 2014 after New York City police used a choke hold on him, said after her son’s death she found it hard to get out of bed. But now she’s on the campaign trail and in the fight for criminal justice reform to help end police brutality.

“I’m turning my mourning into a movement and my sorrow into a strategy,” she said. “Now my pain has a powerful purpose…I think that my calling was to come out here and save someone else’s life, try to save someone else’s son’s or daughter’s life, save the unborn because they are killing us.”

However, the Mothers of the Movement also faced criticism for supporting Clinton by some who believe she doesn’t deserve their endorsement. But Geneva Reed-Veal said she’s spent a considerable amount of time with Clinton discussing policy changes and there is no doubt in her mind that Clinton is sincere about pushing for criminal justice reform and she’s the most qualified candidate to do it.

“Nobody’s asking the movie stars why they’re backing her. Nobody’s asking the big names why they’re backing her,” said Reed-Veal, whose daughter Sandra Bland died in police custody in Texas in 2015. “So why should I have to be put to the fire?”

Despite the criticism and investing a considerable amount of time and their lives to the campaign it’s been worth it to cross the country campaigning to make sure the nation doesn’t forget what happened to their children, Carr said.

“We’re not getting paid for this,” Carr said. “We’re out here. We’re out on the campaign trail. We feel like we can reach millions of people out here on the campaign trail to bring out awareness about our children…The whole United States sees us.”

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