President Joe Biden’s reelection bid won’t be won by million-dollar ad buys or social media sound bites, says U.S. Representative James Clyburn, the man who was key to Biden’s 2020 win.

Republican candidate Donald Trump’s supporters have built a “MAGA wall” online of memes and social media noise that is overwhelming news about Biden’s economic and policy wins, making it impossible to get Democrats’ message across, Clyburn said in a recent interview in his hometown of Columbia, South Carolina.

Clyburn, who at 83 is arguably the most influential Black political voice in the United States, says Biden’s campaign needs to focus more attention on building a historic ground game filled with “voices and validators” who can energize voters and combat a looming disinformation campaign.”If we are going to be successful in this campaign, we are going to have to have what I call hand-to-hand combat, boots on the ground. We are going to have to do what is necessary to circumvent, or smash through that MAGA wall that is being built on sound bites,” Clyburn said, referring to the acronym for Trump’s Make America Great Again slogan.

Asked for comment, Trump campaign spokesperson Steven Cheung said, “Crooked Joe Biden and his allies are scared because they know that no amount of excuses can explain away four years of misery and destruction under their watch.”

Biden is projected to cruise to victory in Saturday’s South Carolina primary election, the first officially sanctioned contest in the Democratic nomination race. He is expected to face Trump in November in a rematch of the 2020 election.

Four years ago, Clyburn effectively resuscitated Biden’s struggling presidential campaign with an endorsement that gave the candidate a comeback primary election victory in South Carolina.

The congressman’s call for an unprecedented ground game – which includes enlisting people to knock on doors and speak at social gatherings – underscores his deep concerns about a looming widespread disinformation campaign.

It also reflects broader concerns over whether Biden, 81, has the skills and charisma needed to sell the public on his accomplishments and the economy. The president spent last summer touring the country to boast about his economic accomplishments, but voters still give him poor marks on the economy.

“So when people tell me what a bad communicator Joe Biden has been, I say to them, don’t confuse goodness with weakness. These are people who basically want to hear a sound bite that makes for a good headline, but that sound bite seldom makes good headway. And Joe Biden is all about making headway,” Clyburn said.

The South Carolina congressman, one several Biden campaign co-chairs, is part of a small group of Democrats that include Barack Obama who are urging Biden to ramp up his campaign efforts and take a more offensive posture against Trump.

The campaign has begun heeding those calls, with Biden invoking Trump much more often and top staffers leaving the White House to bolster the campaign.

Clyburn said he advised the Biden campaign to look at how former Philadelphia Mayor James Kenney, a white Democrat, won two terms in a majority Black city in 2015 and 2019.

“It was boots on the ground. He won that race from door to door,” Clyburn said.

During a recent dinner celebrating South Carolina’s rise to the top of the Democratic Party’s nominating calendar, Clyburn offered evidence of the power of what he calls validators. In the cadence of a pastor, Clyburn preached to the crowd of largely Black supporters about Biden’s accomplishments, often speaking in the local parlance of someone who has spent eight decades in the region.

When Biden took the stage, he quipped: “If I were smart, I’d say thank you and leave. Jim made the case for me better than I can.”