Demonstrators protest against the nomination of Judge Brett Kavanaugh to be a Supreme Court Justice outside of the office of US Senator Susan Collins, Republican of Maine, on Capitol Hill in Washington, DC, September 24, 2018. SAUL LOEB/AFP/Getty Images

In its closing arguments before the November midterm elections, the Republican Party is doubling down on the culture war. "The left" is more than just a threat to conservative policies, according to a new ad released Thursday by the Republican National Committee. Rather, according to the GOP group, it's "an unhinged mob" advocating incivility and even violence. Democrats and liberal commentators have been quick to decry the message as hypocritical, arguing that President Donald Trump himself has explicitly called for violence against his detractors. The RNC has made similar videos in the recent past. But the "mob rule" line of attack appears to have taken root among a growing number of Republicans in Congress, which opponents consider an appeal to Trump's loyal base of supporters. In taking this tack, the ad appears to signal an eleventh-hour shift in Republicans' political messaging, away from legislative issues and toward the cultural fissures dividing Americans.

"Clearly the ad is designed to appeal to Trump's base — no doubt about it," said Barbara Kittridge, founder of progressive strategy group Motive. "The GOP and Trump in particular tends to fan the flames of the culture wars as an attempt to rally the base." An RNC spokesman did not respond to CNBC's inquiries.

'Mob behavior'

The 56-second ad, bathed in a red-orange tinge, links comments from Democratic leaders with the so-called resistance movement against Trump. In recent months, demonstrators have heckled Trump administration associates and GOP lawmakers in public, such as White House advisor Stephen Miller, Texas Sen. Ted Cruz and White House press secretary Sarah Huckabee Sanders. During the multiple rounds of Senate hearings on Brett Kavanaugh's Supreme Court nomination, protesters accosted senators in hallways and elevators. Senate Majority Leader Mitch McConnell, R-Ky., said Thursday on the Senate floor that "only one side was happy to play host to this toxic fringe behavior. Only one side's leaders are now openly calling for more." He added: "We will not let mob behavior drown out all the Americans who want to legitimately participate in the policymaking process." Trump repeated the "mob rule" line on Monday morning, tweeting a quote from right-wing commentator Ben Shapiro. Trump tweet Shapiro The president's charge echoes other Republicans' recent attacks on Democrats. In a radio interview Tuesday, Sen. Rand Paul, R-Ky., said, "I really worry that someone is going to be killed and that those who are ratcheting up the conversation — they have to realize that they bear some responsibility if this elevates to violence." GOP Rep. Dave Brat of Virginia said he was running against the "liberal mob" at a town hall event in May 2017 — a characterization Democrats balked at. Reynolds tweet But Democrats and critics of the GOP have been quick to point out that Trump himself seemed to call for violence on multiple occasions during his campaign rallies. "Trump, more than any leading U.S. figure in recent memory, has actively tried to stoke civil conflict on as many fronts as possible," Greg Sargent, a liberal columnist at The Washington Post, wrote. Trump used such provocative language on the campaign trail in 2016. "If you see somebody getting ready to throw a tomato, knock the crap out of them, would you? Seriously, OK? Just knock the hell," Trump said in February 2016. "I promise you I will pay for the legal fees. I promise, I promise." At two more rallies that month, Trump said of one protester: "I'd like to punch him in the face, I'll tell you." Of another, he said: "Try not to hurt him. If you do, I'll defend you in court. Don't worry about it." At a rally in North Carolina in March, one protester was sucker-punched by an attendee while being escorted out of the building. After he was elected, Trump appeared to encourage the increased use of violence among police officers, saying at a July 2017 speech: "When you see these thugs being thrown into the back of a paddy wagon, you just seen them thrown in, rough. I said, 'Please don't be too nice."

'Unhinged'

The RNC's attack ad shows footage of swarming protesters raging against then-Supreme Court nominee Brett Kavanaugh, spliced with soundbites from prominent Democrats, including former Attorney General Eric Holder, former presidential candidate Hillary Clinton, California Rep. Maxine Waters and House Minority Leader Nancy Pelosi. Holder, who served under President Barack Obama, is seen in the video telling an audience in Georgia that former first lady Michelle Obama's oft-repeated slogan "When they go low, we go high" needs an update for the Trump era. "No, no. When they go low, we kick them," he said. But Holder's clarification was edited out of the RNC's video: "When I say we kick them, I don't mean we do anything inappropriate, we don't do anything illegal, but we have to be tough and we have to fight." In a tweet Thursday, Holder said to "stop the fake outrage." Holder tweet A clip of California's Waters from June follows, in which she urges supporters to "create a crowd" and "push back on" Trump administration officials if they are seen in public. The remarks sparked immediate condemnation from political leaders, including Trump, who labeled Waters, "together with Nancy Pelosi, the Face of the Democrat Party." A snippet from a recent Clinton interview — "you can cannot be civil with a political party that wants to destroy what you stand for, what you care about," she says — precedes Sen. Cory Booker, D-NJ, urging a crowd to "get up in the face of some congresspeople." Republicans denouncing their opponents' rhetoric is far from a recent phenomenon. After Majority Whip Steve Scalise was severely injured by a shooter who stormed a Republican baseball practice in Virginia in June 2017, New York Rep. Chris Collins, one of Trump's earliest supporters in the 2016 election, appeared to blame Democrats for the near-assassination. The gunman's social media posts reportedly expressed fury at Trump's election, and suggest he chose his targets because of his political views. "The finger-pointing, the tone, the angst and the anger directed at Donald Trump, his supporters, really then, some people react to things like that, people get angry as well, and you fuel the fires," Collins said. The New York lawmaker has since pleaded not guilty to insider trading charges lodged by the Justice Department in August. He is continuing his re-election bid.

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