Front-runner Bernie Sanders held a massive rally Thursday in Spartanburg, South Carolina, where he called his campaign a “movement that cannot be stopped.”

Sen. Bernie Sanders: “It is a movement for economic justice, for social justice, for racial justice, for environmental justice. And when millions of people stand up and fight back, nothing on Earth can stop us.”

Sanders also rallied Thursday at Winston-Salem State University in North Carolina, where he led a march of hundreds of students to an early-voting site. Later Thursday, thousands of Sanders supporters packed a rally in Richmond, Virginia — another Super Tuesday state.

The New York Times interviewed dozens of Democratic establishment leaders who will serve as “superdelegates” at the party’s nominating convention in July, and found the vast majority are so opposed to Bernie Sanders’s candidacy, they’re willing to risk damage to the Democratic Party. Of 93 superdelegates surveyed by the Times, nearly all said they would vote against Sanders in a brokered convention, if Sanders were to arrive with a plurality — and not a majority — of pledged delegates.

Many of the superdelegates are corporate lobbyists with healthcare clients opposing Sanders’s Medicare for All legislation. The Intercept’s Lee Fang reports one of them, Democratic National Committee member William Owen, donated exclusively to Republican Senate candidates during the last election cycle — including an $8,500 contribution to a joint fundraising committee designed to benefit Senate Majority Leader Mitch McConnell. Owen is backing former Vice President Joe Biden for the Democratic nomination in 2020.