Republican presidential candidates are spreading the messages of booming right-wing hate groups, the Southern Poverty Law Center said Wednesday.

SPLC has released its annual report on domestic extremism, noting that the number of right-wing hate groups grew 14 percent to almost 900 and anti-government “Patriot” groups grew to almost 1,000 in 2015. Not only is organized hate growing, it is getting a wide audience thanks to the GOP race.

Candidates like Donald Trump are mimicking voices that “at any other time would’ve been considered incredibly extreme,” said SPLC President Mark Potok. “Trump retweeted a neo-Nazi’s claim that black people are responsible for 80-some-odd percent of murders of white people.”

“Bush joined in the Muslim-bashing, saying yes, we can admit some Syrian refugees, but only Christian refugees,” Potok said, adding that this makes Jeb Bush a relative moderate in the race.

And the SPLC warns that many on the radical right might not be joining brick-and-mortar groups at all. The group sees alleged Charleston church shooter Dylann Roof as a new breed of white supremacist, who—like many Western jihadis—finds like-minded individuals online without ever meeting them in person.

“We think the movement, the radical right movement in general, is bigger than our numbers suggest,” Potok said. In addition to those participating in cyberspace, Potok said he thinks “an enormous number of real radical hatred has been absorbed into the political mainstream.”

“We have real enablers in the political mainstream who are helping the ideas of the radical right grow,” Potok said. “We are living in an era of incredible political irresponsibility.”

Many conspiracy theories that originated on the far right have also found their way into conventional public discourse thanks to the Republicans. Take for instance Rand Paul’s claim that Common Core education standards are a socialist conspiracy, which came from the radical John Birch Society. A voluntary sustainable development plan called Agenda 21 has been transformed by Ted Cruz into a plan that “will result in the elimination of all paved roads, and, God forbid, golf courses,” Potok said.

“Certainly conspiracy theories have been a part of American political life since the very earliest days,” Potok said, but he added that the level seen now is “unprecedented.”

Yet not all radical groups saw equal growth in 2015. White nationalists, racist skinheads, and even neo-Nazis saw a decline, while black separatist groups grew from 113 to 180 last year. Klan groups more than doubled in the same timespan, from 72 in 2014 to 190 last year.

Black separatist groups grew largely in response to attention to police violence against black men, in particular, Potok said. Many of them are Black Israelite groups, “a rather bizarre theology, but more widespread than many people believe,” that believes black Americans are the descendants of the lost tribes of Israel.

“Groups that are anti-white, anti-gay, and anti-Semitic as a rule,” he said of the Black separatist groups.

In contrast, Potok cautioned that the growth in Klan groups may be overblown: The Klan world is small, and the growth in groups may be largely a matter of larger groups breaking up and re-organizing in smaller incarnations. Many of them saw 2015’s battle against the Confederate Flag as a “call to arms,” he said.