Richard Trumka, the president of the AFL-CIO, thought he’d have a pretty simple job in 2016: turn out his 12.7 million union members to support the Democratic presidential nominee.

But it turns out Trumka’s task may be very different and perhaps more difficult: preventing a significant share of union households — which typically favor Democrats in elections — from defecting to Donald Trump if he’s the GOP standard-bearer.

“If left unattended, the anger and the frustration [Trump has] tapped into will carry the day,” Trumka warned Monday in an interview with the Washington Post. “But when you give working-class people the facts, I think he falls apart. He’s a house of cards.”

Trumka has an anti-Trump plan, the first parts of which will roll out next week: educate voters about what he says is Trump’s history of anti-worker, anti-union policies. That campaign — on which he would not put a price tag, but unions spent more than $9.3 million in the 2012 presidential race —  will eventually evolve into uniting labor voters behind a Democratic candidate.

The campaign will be focused on grassroots contact with union members and potential Democrats to argue that Trump wants to cut workers’ wages and that his immigration and unionization policies  would leave them worse off than they are today. Trumka said unions plans to work  directly with activist groups, like the growing movement for a $15 minimum wage, that have already had success driving people to rally and vote.

“We’ll have literally millions of phone calls, leaflets, door knocks, rallies and seminars,” Trumka said.

Labor groups have fallen behind conservatives in recent years in driving voters to the polls when it counts, and they’ve also had a difficult time keeping those they do elect loyal.

“We’ve allowed ourselves to be beat…year after year after year,” Trumka admitted.

Trump is not the AFL-CIO’s only target. After years of declining membership and shrinking influence,  the nation’s largest labor union and a network of other progressive groups plan to play in key races across the country. The group intends to focus time, energy and money on five to seven states, which could include Pennsylvania, Ohio, Florida, Nevada, Wisconsin and Missouri. All of those states have strong labor presence and are home to competitive Senate battles in November.

The typically reliable Democratic union vote has been torn this year with members mainly divided between Trump, Sen. Bernie Sanders and Hillary Clinton. The surprising results have many questioning the conventional wisdom that an establishment Democrat like Clinton should dominate in working-class, union enclaves that cluster in and around the cities and suburbs of the Midwest.

The AFL-CIO has been doing its research and it is clear that Trump is a credible threat

Trumka said he believes even the voters who have cast ballots for Trump are still winnable for labor. He said the AFL-CIO has been doing near-daily polling, testing out different messages and angles for convincing Trump supporters to return to the Democratic fold.  “When you go in and tell them the truth you’ve got a yardstick to measure,” he said. “It’s like focus groups almost.”

But it’s also true that all kinds of attacks — though just now picking up speed — thus far have been unable to significantly damage Trump. Jeb Bush tried, and dropped out of the race after a poor showing in South Carolina, and Sen. Marco Rubio (R-Fla.) is fading after engaging in the same verbal insults that Trump has often hurled at his competitors.

Over the course of five weeks in December and January, canvassers from the group’s community affiliate, Working America, reached out to likely voters in households with earnings of $75,000 or less located in typically blue-collar neighborhoods near Cleveland and Pittsburgh. While more than half  the voters surveyed were still undecided, a third of those who had chosen a candidate supported Trump. One in four Democrats said they backed Trump.

More troubling to labor is that Trump won 36 percent of independents in Michigan’s primary on Tuesday, according to exit polls conducted by CNN. He also won 37 percent of Republican voters who identify as moderate.

These are the type of voters that Trumka plans to court. He wants to convince them to focus on the candidates who have the best chance of actually enacting their campaign promises instead of  simply “Making America Great Again.”

“I would not try to dissuade a voter from thinking big or thinking what the country can be. That’s been done too much,” Trumka said. “We need to give [voters] alternatives point for point—wages, taxes, making the rich pay.”

Labor groups plan to spell out how Trump’s economic policies and positions would hurt workers even if his protectionist message — slapping a 45 percent tariff on Chinese exports, quashing undocumented immigration and denouncing the Trans-Pacific Partnership — seems enticing.

Some of Trump’s talking points do play into the union’s hands. Trump said in a November debate that American “wages are too high.” Last month in an interview with South Carolina Radio Networkhe said he can live with unions but his “position on right to work is 100 percent,” a reference to backing states that have statutes that prohibit some union activities.

Furthermore, Trump’s business empire has often had to tangle with union workers, especially in his home state of New York. In December, Trump also began efforts to block workers at his Las Vegas hotel from unionizing. The incident has not yet become part of the national conversation but Trumka intends to change that.

Trumka also points to Trump’s plan to build a wall on the border with Mexico and his pledge to deport millions of Muslims as incontrovertible sound bites that can be printed on mailers, chanted at rallies and used to hammer home the point that a President Trump would spell disaster for the working class.

The union plan is not limited to an anti-Trump revolution. Trumka said it is no mistake that the states he named all have competitive gubernatorial or Senate races. He plans to use each state’s network of progressive groups and unions to pressure candidates running for Senate, House and state legislature into adopting pro-union positions. Those groups will also be in charge of local ad buys, door knocking and phone banking to remind voters of the allegedly pro-trade, anti-worker records of incumbents like Republican Sens. Pat Toomey (Pa.) and Ron Johnson (Wis.).

Trumka said the tactics are already working in Ohio where Republican Sen. Rob Portman, a former U.S. trade representative, announced he would not support the 12-nation Pacific Rim trade agreement known as the Trans Pacific Partnership.

Republican aides laughed off the idea that Portman shifted his position under labor pressure.

“For more than two years, Rob outlined his concerns and objections and made clear that his support was always contingent on ensuring that a final agreement give Ohio workers a level playing field, increase exports, and create more jobs,” said Portman spokesman Kevin Smith. “Unfortunately, the TPP negotiated by the Obama administration does not accomplish those goals.”

Toomey also scoffed at the idea that labor spending and influence are anything new in his home state of Pennsylvania. He said nothing will change even if Trumka’s plan for a bigger, better labor drive does succeed.

“I have from the beginning assumed that the left would be spending a significant amount of time and money,” Toomey said. “We know this is going to be a battle — but it’s Pennsylvania in an election year.”