One of the nation's most influential labor union says it revving up its fight against Republican presidential front-runner Donald Trump to keep him out of the White House. Mary Kay Henry, president of the Service Employees International Union, said she has directed her 2.1 million members to help defeat the business mogul who has won over many working-class voters.

In an interview with David Axelrod on his podcast "The Axe Files," out Thursday, Henry said her organization is going into “hyperdrive” because Trump appeals to some of her members because of the “terrible anxiety” some people in the working class feel. "This is a very dangerous political moment in our country,” she said. “I think he’s touching this vein of the terrible anxiety that working-class people feel about their current status, but more importantly, how terrified they are for their kids not being able to do as well as they have, never mind doing better."

Henry said she was working to persuade union members that Trump would not represent their best interests. "We’re doing one-on-ones with every one of our members right now in this period, because 64 percent of our public members identify as conservative and are much more interested in the Republican debate than the Democratic debate at this moment," she said, according to Politico.

The union endorsed Democratic front-runner Hillary Clinton in November. At the time, Henry said that, “Hillary Clinton has proven she will fight, deliver and win for working families. SEIU members and working families across America are part of a growing movement to build a better future for their families, and Hillary Clinton will support and stand with them."

SEIU leaders have been vocal about their views on Trump in the past. In November, the union launched an ad campaign accusing Republican presidential candidates, including Trump, of attacking immigrants. “Now it’s time for our community to say no. We will not accept hate. We will not allow anti-immigrant attacks,” said a male narrator in the 30-second ad.