Washington (CNN) Sen. Bernie Sanders denounced a web ad recently put out by President Donald Trump's reelection campaign, which called Democrats "complicit in every murder committed by illegal immigrants."

"It is really unbelievable and so sad for our country that we have a President of the United States that says such nonsense and such outrageous statements," the Vermont Independent, who caucuses with Democrats, said on CNN's "State of the Union" Sunday morning.

The ad was released hours into the government shutdown. The largest point of contention between political parties that led to the government shutdown was immigration policy -- including the funding for a proposed border wall and the future of the Deferred Action for Childhood Arrivals (DACA) program, which has protected undocumented immigrants brought to the United States as children from deportation.

"They need a path toward citizenship," Sanders said, referring to the beneficiaries of DACA, known as Dreamers. "Then you see a President put something like that on the air, trying to divide us up, trying to foment hatred. It is really sad."

Sen. Dick Durbin, D-Illinois, said on ABC's "This Week" that the rhetoric used in the Trump ad "doesn't work," citing Republican Ed Gillespie's failed gubernatorial campaign ads , which attacked now-Virginia Gov. Ralph Northam for voting "in favor of sanctuary cities that let dangerous illegal immigrants back on the street" and linking his vote to the rise of the violent gang MS-13.

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