GREENVILLE, S.C. – Former Vice President Joe Biden has a sizable lead in the South Carolina Democratic presidential primary, according to results of Clemson University's Palmetto Poll released Wednesday morning.

Biden received support from 35% of the poll's respondents, said Clemson University political science professor Bruce Ransom. Tom Steyer was a distant second with 17%, and U.S. Sen. Bernie Sanders of Vermont was third with 13%. U.S. Sen. Elizabeth Warren and Pete Buttigieg, the former mayor of South Bend, Indiana, each had 8%. U.S. Sen. Amy Klobuchar of Minnesota had 4% and U.S. Rep. Tulsi Gabbard of Hawaii had 2%.

The Palmetto Poll, which Clemson has conducted since 1999, shows Biden with a larger lead in South Carolina than several other recent polls.

This version of the Palmetto Poll is based on responses from 650 voters. The respondents included 65% women and 57% black people. The poll has a 3.8% margin of error.

"Joe Biden is perched to achieve his goal of South Carolina becoming a firewall," Ransom said.

The former vice president needs a victory in the state's first-in-the-South primary after lackluster showings in the Iowa caucuses and New Hampshire primary and a second-place finish in last week's Nevada caucuses.

The Palmetto Poll was conducted before Biden received an endorsement earlier Wednesday from U.S. Rep. James Clyburn, the dean of South Carolina's congressional delegation and the highest-ranking black Democrat in the House of Representatives.

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"We have great confidence that even though this is kind of out of step with some other polls, it is right in step with how people are going to vote here in South Carolina," said David Woodard, a retired Clemson University political science professor.

"I don't want us to beat our chest too much, but in the years that Bruce and I have been doing this, we've always called it right," Woodard said.

Woodard said the Palmetto Poll has developed a reputation for accuracy because it samples voters who cast ballots in the last primary, newly registered voters and voters who say they are going to vote in the upcoming primary.

Woodard noted that Steyer "has not been on the radar" in the previous Democratic contests in Iowa, New Hampshire and Nevada. But Steyer has spent more than $18 million in South Carolina, mostly on TV and internet advertising, according to media reports.

"Those of us who live here know how he's been on television and been visiting around, and we think he is going to be a presence here in the South Carolina primary," Woodard said.

The poll found that Sanders, who built momentum with wins in New Hampshire and Nevada, may be poised for a second consecutive poor showing in South Carolina, where he was soundly defeated by Hillary Clinton in 2016.

While the poll found Sanders is in third place, Woodard said he was surprised to see that the Vermont senator does have some support among voters in their 40s and even older.

"He has more than just youth support," Woodard said.

Among the Democratic candidates, Sanders is dominating the online conversation — but positive and negative views of him are almost evenly split, said Will Henderson, associate director of Clemson's Social Media Listening Center.

Follow Kirk Brown on Twitter @KirkBrown_AIM