(Bloomberg) -- The highest-ranking African-American in Congress warned that if Bernie Sanders is the 2020 Democratic nominee the party could lose many of the moderate seats they won to retake the House in 2018.

“It’s going to be tough to hold on to these jobs if you have to make the case for a self-proclaimed democratic socialist,” House Majority Whip James Clyburn said on ABC’s “This Week.” Many voters are “leery” of the socialist label, he added.

Democrats won a majority in the House in 2018 with the party’s largest gain in the chamber since 1974. Some of the seats flipped in that election had been held by Republicans for years, and were in districts won by President Donald Trump in 2016.

Clyburn said he will endorse a candidate following the Tuesday night Democratic debate in South Carolina.

On NBC’s “Meet the Press,” Clyburn said he’s worked closely with Sanders, the Vermont senator, on many issues and he “brings a lot to the table for people to consider.” But he again mentioned the democratic socialist label.

“That word has always had really dire consequences throughout South Carolina,” Clyburn said.

Establishment Alarm

Clyburn, meanwhile, said former Vice President Joe Biden could have done better during the various candidates’ debates, and that Elizabeth Warren “did herself a lot of good” in last week’s debate in Nevada.

He suggested the winner of the Feb. 29 South Carolina primary could surge into Super Tuesday.

“South Carolina has a demographic that lends itself well to Democratic voters especially,” he said. “If you can win South Carolina decisively, I think it will set the stage for Super Tuesday and you will become the odds-on favorite.”

Biden is leading in the state in a RealClear Politics average of recent polls, with Sanders trailing by just 3 percentage points.

Other establishment figures in the Democratic Party have been sounding the alarm about Sanders’ rise. Rahm Emanuel, the former Chicago mayor, House member and White House chief of staff for Barack Obama, called a Sanders nomination “fraught with political risk” on “This Week.”

Emanuel noted that none of the Democrats who flipped seats from Republicans in 2018 have endorsed Sanders. Other candidates need consider dropping out so the party can coalesce around a single alternative to Sanders, Emanuel said, without specifying who that person should be.

To contact the reporter on this story: Steven T. Dennis in Washington at sdennis17@bloomberg.net

To contact the editors responsible for this story: Kevin Whitelaw at kwhitelaw@bloomberg.net, Ros Krasny, Linus Chua

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