Down in the polls and struggling with minority voters in the early primary states, Bernie Sanders is taking a page out of rival Hillary Clinton’s playbook by throwing punches at a prime target for progressives and Hispanics: Donald Trump.

At a Las Vegas forum on immigration reform Monday, the Vermont senator and underdog presidential candidate said that while he respects differences of opinion on immigration, he “[does] not respect people like Donald Trump, who are appealing to racism and xenophobia to win votes.”

“That is unacceptable,” Sanders said, promising to fight “tooth and nail” against Trump’s controversial views about Mexican immigrants.

For months, Sanders has shied away from directly targeting the Republicans running for president, preferring instead to tar the entire field with broad-brush criticisms about their billionaire-friendly policies. But in the last two days, Sanders has started unloaded on Trump at every turn.

In a campaign speech in North Las Vegas on Sunday, Sanders tore into Trump’s promise to deport most illegal immigrants. “That is old-fashioned racism,” he said. “We will not tolerate it. It is not an American value to talk about rounding up millions of people and simply say that we are going to throw them out of the country. That is xenophobia.”

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He deliberately singled out Trump on economic issues, as well. “We have to create an economy that stands for all us, not just Donald Trump and his billionaire friends,” he told the predominantly Hispanic crowd on Monday.

#share#Though Sanders does well with white Democratic voters — especially those under 30 — his campaign is struggling to connect with African-American and Hispanic voters in South Carolina and Nevada, respectively. His recent focus on Trump’s “racism” could be part of a plan to drum up support in the latter demographic, especially when coupled with the promise he made Monday to prioritize comprehensive-immigration reform in his first 100 days as president.

#related#If that is Sanders’s plan, he’s late to the party. Though once a guest at Trump’s most recent wedding, Hillary Clinton has beaten him like a piñata for weeks on end. In July, she called out Trump in Iowa for “the hate he is spewing about immigrants and their families.” In September, she went on The Tonight Show to lampoon the then-GOP front-runner. And she appeared at a union picket outside his Las Vegas hotel before the Democratic debate in October, urging workers to “say no to Donald Trump.”

It seems to be working. After a summer in which she struggled to pull away from Sanders, hampered by a slow-burning e-mail scandal, questions about conflicts of interest at the Clinton Foundation, and unexpected enthusiasm for the Vermont senator, the former secretary of state has opened up commanding leads in Iowa, New Hampshire, and nationwide over the past few weeks.

— Brendan Bordelon is a political reporter for National Review.