Take, for example, when Ted Cruz dropped out of the presidential race in May. Conservatives came out in full swing against Trump, in some cases going so far as to pronounce Hillary Clinton the winner in November and burn their voter-registration cards. Bryan Akner, a 40-year-old Cruz supporter who lives in West Palm Beach, Florida, was among them. “Every time I hear him (Trump) speaking, I never hear ‘Constitution,’ I never hear ‘liberty,’ I never hear ‘freedom.’ It’s always fear-mongering pretty much to me and playing on the uneducated or under-informed people,” he said. Akner has been a registered Republican since 1993, but after Cruz exited the race, he decided to disaffiliate, frustrated with what he believes to be the party’s slow drift away from conservative to moderate. “It was the last straw on the camel’s back for me,” said Akner. Disillusioned by the party, Ben Kopciel, a 32-year-old Cruz supporter who lives in Brooklyn, New York, also decided to drop his Republican affiliation after 12 years. “I voted based on values,” Kopciel said. “I’ll vote for some values over nothing, but I won’t vote for no values.”

Around the country, 25 percent of Americans identify as Republicans as of April 2016, according to a Gallup survey, while a separate analysis found that 20 states are “solidly or leaning Republican.” But the number of registered Republicans in some states has decreased. In California, which holds its primary next week, 27 percent of voters are registered as Republican, down from 30 percent in 2012 and 33 percent in 2008, according to records from the California Office of the Secretary of State. A similar trend has unfolded in New York, where Republican registration has also dropped.

Nevertheless, a majority of those still identifying as Republican voters want their party to back Trump, according to a New York Times/CBS News poll. Broken down, this race has shown that there are registered Republican voters who are loyal to the party, those who are staunch supporters of Trump, and those who have reservations about a candidate who doesn’t hold conservative values. But these fractures are not unprecedented.

In 1964, Barry Goldwater also rattled the party. Then, Republicans rebuked Goldwater. A Lyndon Johnson campaign ad titled “Confessions of a Republican” expressed grievances with Goldwater. “If you unite behind a man you don’t believe in, it’s a lie,” the man says in the four-minute ad. The ad was intended to coalesce support behind Johnson, serving as an example of a time when voters faced a divisive candidate.

In 1966, California Republican Party Chairman Gaylord B. Parkinson established the “11th Commandment.” It said: “Thou shall not speak ill of any Republican.” He added: “Henceforth, if any Republican has a grievance against another, that grievance is not to be bared publicly.” The commandment continues to thrive among Republicans today. The Republican National Committee has called for unity and relayed confidence in the party. GOP Chairman Reince Priebus has defended Trump, saying the presumptive nominee is “trying” to bring the party back together. And most recently, House Speaker Paul Ryan, the party’s highest-ranking official, said he’ll vote for Trump in November.