/www.huffingtonpost.com/news/donald-trump/"}}">Donald Trump’s ongoing effort to convince his supporters that the election is rigged is a dangerous threat to American democracy and the media needs to call him out, CNN’s Brian Stelter said Sunday.

In an address delivered during his show “Reliable Sources,” Stelter pointed out that the Republican nominee’s attempts to discredit the election system over the last year haven’t received as much attention from reporters recently, as such comments have become par for the course. That, Stelter argues, needs to change.

“[O]ver time, the repetition, Trump’s lies about election rigging have become a form of background noise, more of the same, and this is a propaganda technique, whether Trump knows it or not,” he said. “If you say something often enough, if you plant enough seeds, people start to wonder, ‘Will my vote matter? Will it actually count?’”

As an example, Stelter pointed to a clip of Trump hinting at voter fraud and crooked polls during a speech in Philadelphia on Monday. That clip was only played once on CNN.

“We as a country cannot allow ourselves to become numb to this,” Stelter urged, noting that there is zero evidence of such fraud. “We as a media cannot shrug it off as old news ... Some of his supporters believe him.”

Trump is encouraging his supporters to act as poll monitors in battleground states, and his efforts to cast doubt on the election system have inspired some supporters to call for a “revolution” if he loses the election on Nov. 8, clips played by Stelter showed.

“Mr. Trump, think of your children,” Stelter concluded. “America is great partly because everyone accepts the results of elections, for decades in the past and hopefully for decades to come. Inventing a conspiracy theory is no way to make America great again.”

Editor’s note: Donald Trump regularly incites political violence and is a serial liar, rampant xenophobe, racist, misogynist and birther who has repeatedly pledged to ban all Muslims — 1.6 billion members of an entire religion — from entering the U.S.