Moms of Trayvon Martin, Eric Garner to stump for Clinton

Bernie Sanders Vows to Keep Fighting Hillary Clinton
Bernie Sanders Vows to Keep Fighting Hillary Clinton

The mothers of Trayvon Martin, Sandra Bland and Eric Garner were set to join Hillary Clinton at a South Carolina town hall on Tuesday as she jockeyed with rival Bernie Sanders for African-American voters.

The issue of racism and the treatment of minorities at the hands of the justice system have been major themes of the Democratic campaign. The women appearing with Clinton — who have lost children in brushes with police or to violence — were due to make the case that the former secretary of state would take on the gun lobby, a campaign official told NBC News.

Clinton's advantage among blacks will have deep implications beyond Saturday's South Carolina vote with Super Tuesday looming on March 1.

Sybrina Fulton is the mother of Trayvon Martin, who was shot and killed by George Zimmerman in Florida on Feb. 26, 2012. Geneva Reed-Veal is the mother of Sandra Bland, who was found dead in a Texas jail cell on July 13, 2015. Gwen Carr is mother of Eric Garner, who died after being held in a choke hold by police on July 17, 2014, in New York.

Hillary Clinton and Bernie Sanders at a town hall event in Las Vegas:

However, Eric Garner's eldest daughter Erica endorsed Sanders on January 29.

On Tuesday, the Sanders campaign released an ad featuring director and activist Spike Lee endorsing the Vermont senator.

Related: Clinton Gains Support from 170 African American Women Leaders

Gabby Giffords, a former Arizona Congresswoman shot in the head at a 2011 event in Tucson, will also join the former first lady on Tuesday.

A recent NBC News/Wall Street Journal/Marist poll of South Carolina Democrats showed that older black voters were more pro-Clinton than their younger counterparts. Sanders was much closer among blacks under 45, with 35 percent of the vote.

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