Several mainstream Republican Senate candidates are drawing on the “great replacement” conspiracy theory once confined to the far-right fringes of U.S. politics to court voters this campaign season, promoting the baseless notion that there is a plot to diminish the influence of white people in America.

In some cases, the comments have gone largely overlooked given the hard-line immigration rhetoric that has become commonplace among conservatives during the Trump era. But a weekend mass shooting in Buffalo, New York, that may have been inspired by the racist theory is drawing new attention to the GOP’s growing embrace of white nationalist creed.

Three weeks ago in Arizona, Republican Senate candidate Blake Masters accused Democrats of trying to flood the nation with millions of immigrants “to change the demographics of our country.” A few days later in Missouri, Senate hopeful Eric Schmitt, the state attorney general, said Democrats were “fundamentally trying to change this country through illegal immigration.” And in Ohio, Republican Senate nominee JD Vance accused Democrats of trying to “transform the electorate.”

Warning of an immigrant “invasion,” Vance told Fox News Channel that Democrats “have decided that they can’t win reelection in 2022 unless they bring a large number of new voters to replace the voters that are already here.”

Some of the Republican campaigns denied that their statements amounted to replacement theory, but among the experts, there is little question.

Five experts on hate speech who reviewed the Republican candidates’ comments confirmed that they promote the baseless racist theory, even though the Republicans don’t mention race directly.

“Comments like these demonstrate two essential features of great replacement conspiracy theory. They predict racial doomsday, saying that it is all part of an orchestrated master plan. It’s only the language that has been softened,” said American University professor Brian Hughes, associate director of the Polarization and Extremism Research and Innovation Lab. “The basic story they tell is the same one we see in white supremacist chats across the internet: An enemy is orchestrating doom for white Americans by plotting to fill the country with nonwhites.”

Indeed, a mainstream interpretation of replacement theory in the U.S. baselessly suggests Democrats are encouraging immigration from Latin America so more like-minded potential voters replace “traditional” Americans, says Mark Pitcavage, senior research fellow at the Anti-Defamation League Center on Extremism.

Such a message has become a central component of the modern-day conservative movement’s appeal to voters. Former President Donald Trump repeatedly warned of an immigrant invasion on the southern border, and he was slow to condemn white supremacy throughout his presidency.

Shortly after taking office, Trump shared a social media post from someone with the username WhiteGenocideTM.

Replacement theory is being investigated as a motivating factor in the Buffalo supermarket shooting, which killed 10 Black people and left three other people injured.

President Joe Biden condemned replacement theory directly — and those who spread it, although he did not name names — after meeting with victims’ families Tuesday in Buffalo.

“Hate, that through the media, and politics, the internet, has radicalized angry, alienated, lost and isolated individuals into falsely believing that they will be replaced — that’s the word, ‘replaced’ — by the others, by people who don’t look like them,” Biden charged.

“I call on all Americans to reject the lie,” the Democratic president continued. “And I condemn those who spread the lie for power, political gain and for profit.”

Rep. Liz Cheney, who was ousted from House Republican leadership for her outspoken criticism of Trump, blamed her own party on Monday for enabling “white nationalism, white supremacy and anti-Semitism.”

“History has taught us that what begins with words ends in far worse,” Cheney tweeted. GOP “leaders must renounce and reject these views and those who hold them.”

Senate Republican leader Mitch McConnell was asked three times Tuesday, in different ways, about replacement theory — if leaders have to speak out about it or believe it themselves — and declined to fully respond.

“Well, certainly the episode of this horrible episode in Buffalo is a result of a completely deranged young man who ought to suffer severe as possible penalty under the law,” he said.

Asked about Biden’s call to reject the lie, McConnell shifted responsibility more broadly: “Racism of any sort is abhorrent in America and ought to be stood up to everybody, both Republicans, Democrats, all Americans.”

In a poll released last week, The Associated Press-NORC Center for Public Affairs Research found that about 1 in 3 Americans believes an effort is underway to replace U.S.-born Americans with immigrants for electoral gain.

Fox News’ most popular personality, Tucker Carlson, has been one of the theory’s biggest proponents. A study of five years’ worth of Carlson’s show by The New York Times found 400 instances in which he talked about Democratic politicians and others seeking to force demographic change through immigration.

But so far, at least, less attention has been focused on Republican candidates preparing to face voters in the coming weeks and months who have, in some cases, promoted the theory again and again.

In interviews with conservative national television and radio over the last year, Wisconsin Sen. Ron Johnson has called replacement theory “the Democrat grand plan.”

“I’ve got to believe they want to change the makeup of the electorate,” he told a Minneapolis-area conservative radio host last month.

Johnson condemned the “horrific” Buffalo attack on social media, while campaign spokesperson Alexa Henning called it a “lie” that he supports replacement theory.

“The senator has spoken extensively on the inhumanity of the Biden administration’s open border policies, not some racist ‘theory,’” she said.

In Missouri, at least two Republicans vying for the Republican Senate nomination have made similar statements more recently.

While touring the U.S.-Mexico border last month, former Missouri Gov. Eric Greitens said that immigrants crossing over illegally were “flooding into all of the 50 states, and that includes Missouri.”

“What’s also very clear is that Joe Biden’s policies are an assault on the entire idea of America,” Greitens said. “He’s wiping out the distinction between citizens and non-citizens, and he’s doing it on purpose.”

A week later, Schmitt, Greitens’ Republican rival, claimed that tens of millions of immigrants were crossing into the U.S. illegally because of Biden’s policies. He said Democrats were intentionally encouraging illegal immigration for their own benefit.

“They are fundamentally trying to change this country through their illegal immigration policy,” Schmitt told conservative commentator Glenn Beck.

On Tuesday, Schmitt criticized reporting that he had promoted replacement theory as “woke ‘journalism.’”

“I’ll never stop fighting for border security or calling out the Democrats’ radical agenda. We’ve got a country to save,” he tweeted.

Greitens ignored questions about replacement theory but called the mass shooting in Buffalo “truly horrific” in a written statement.

In Arizona, Masters has warned throughout his campaign of a Democratic plot to transform the U.S. electorate.

“Obviously, the Democrats, they hope to just change the demographics of our country,” Masters told the Patriot Edition podcast late last month. “They hope to import an entirely new electorate. Then they call you a racist and a bigot.”

In Ohio, Vance has already secured a place on the November ballot. He won Trump’s endorsement after embracing many of the former president’s hardline views, including those related to immigration.

Vance told Breitbart News last month that Democrats are trying to give 15 million immigrants in the country illegally the right to vote. “They are trying to transform the electorate of this country,” he said.

He made similar comments days later at a town hall in Portsmouth, Ohio.

Shortly after Biden was inaugurated, congressional Democrats proposed legislation that would include an eight-year pathway to citizenship for the estimated 11 million people living in the country illegally, but the proposal has stalled and has little chance of clearing Congress.

“Now of course,” Vance said, “you’re accused of being a racist to even point this out. We get to decide, the people get to decide how we do or do not transform the country.”

The Vance campaign declined to comment.