Democratic candidates have singled out Bernie Sanders as the front-runner heading into South Carolina’s presidential primary this weekend. With the high ratings has come multiple negative campaign ads targeting Sanders.

South Carolina has a high percentage of African American voters, and groups are courting their votes.

"Socialist Bernie Sanders is promising a lot of free stuff," reads a brochure sent to 200,000 black voters in South Carolina. "Nominating Bernie means we reelect Trump. We can't afford Bernie Sanders."

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The flyers were distributed by The Big Tent Project, a new organization trying to promote moderate candidates. It has $1 million to spend, according to Politico.

Former Vice President Joe Biden, former South Bend, Indiana, Mayor Pete Buttigieg and former New York Mayor Mike Bloomberg have launched advertisement attacks for the first time this week, according to The Associated Press.

On Monday, Buttigieg released a 30-second advertisement launched on South Carolina televisions that called out some of Sanders' health care policies.

"Bernie Sanders' 'Medicare for All' would completely eliminate private insurance, forcing 150 million Americans off their current plans, more than 22 million seniors on Medicare Advantage. Pete Buttigieg has a better way...Instead of polarization, progress." — Pete for America television ad

Biden released an online advertisement that accused Sanders of interfering in President Barack Obama’s 2012 reelection attempt.

"I think it would be a good idea if President Obama faced some primary opposition," Sanders is quoted saying in an audio clip. "When it comes to building on President Obama's legacy, Bernie Sanders just can't be trusted," the narrator finishes.

CNN reported that roughly 1 in 3 South Carolina Biden-backers in a recent poll said they might vote for another candidate Saturday. Biden is projected to win the African American vote ahead of Sanders.

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Former Vice President Joe Biden is trying to get South Carolina voters to question Bernie Sanders’ loyalty to former President Barack Obama.

Credit: Gerald Herbert/AP

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Credit: Gerald Herbert/AP

Bloomberg chimed in with a video advertisement on Twitter on Monday, claiming “We deserve a president who is not beholden to the gun lobby.”

The 90-second advertisement pulls evidence from Sanders' first run for the Senate, when he had the backing of the NRA. ABC News reported Sanders now has an "F rating" from the pro-gun organization and has been endorsed by school shooting survivors for his current gun control policies.

Sanders’ campaign team isn’t concerned heading into Saturday’s primary.

Real Clear Politics has pulled data from three polls. Recent results show Biden in the lead across the board, with an average 8-point spread between him and second-place Sanders.

Jeff Weaver, Sanders’ senior adviser, said there was an “air of desperation” to the recent advertisement attacks.

“You’ve got candidates, you’ve got super PACs, all piling on to stop Bernie Sanders,” Weaver said. "They know he has the momentum in the race.”

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