A major union representing immigration and law enforcement officials endorsed GOP nominee Donald Trump for president Monday, saying Democratic nominee Hillary Clinton’s immigration proposals make up the “most radical immigration agenda” in U.S. history.

The National Immigration and Customs Enforcement Council represents 5,000 federal immigration officers and law enforcement staff described by its President Chris Crane in the endorsement as the “last line of defense for American communities.” The move comes ahead of a highly anticipated presidential debate Monday, and is the union’s first ever endorsement of a presidential candidate.

Clinton won just 5 percent of support from the union in a vote on the endorsement, Crane said in a statement Monday, citing her unwillingness to meet with the union and her embrace of immigration policies championed by President Barack Obama that have prevented them from doing their job.

“Donald Trump reached out to us for a meeting, sat down with me to discuss his goals for enforcement, and pledged to support ICE officers, our nation’s laws and our members,” he said, referring favorably to Trump’s plan to up border security, end Sanctuary Cities and undo Obama’s executive orders on immigration granting special benefits to millions of illegal immigrants.

Clinton has pledged to uphold and even expand Obama’s executive orders on immigration, and wants to grant citizenship to the vast majority of illegal immigrants already in the country. She would also dramatically expand the number of immigrants who come to the country legally, at a time when those levels are on track to exceed historical precedent in both size and proportion of the population.

“[Clinton] has promised the most radical immigration agenda proposal in U.S. history,” Crane added. “Her radical plan would result in the loss of thousands of innocent American lives, mass victimization and death for many attempting to immigrate to the United States, the total gutting of interior enforcement, the handcuffing of ICE officers, and an uncontrollable flood of illegal immigrants across U.S. borders.”

The endorsement is a boost for Trump ahead of a debate expected to have a big impact on undecided voters. Some 34 percent of registered voters said the debates will be “very important” in their decision, according to a Wall Street Journal/NBC News poll released Sunday. The poll found 11 percent of voters to be “debate persuadables,” in that they think the debate is important and don’t have strong ties to either Clinton or Trump.

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