Jae C. Hong / AP

Donald Trump’s surge has been anything but subtle. He climbed the polls throughout the primary season while his rivals exited the race one by one. His controversial rhetoric rarely made a dent on a campaign built on ardent, loyal supporters. And now, Trump’s candidacy is complicating the relationship between party identification and party allegiance within the GOP.

Historically, party identification is weaker among Republicans than Democrats. A Pew Research analysis released in 2015 found 23 percent of Americans identify as Republicans compared with 32 percent who identify as Democrats. The findings align with a pattern in the United States. As Pew put it: “For more than 70 years, with few exceptions, more Americans have identified as Democrats than Republicans.” But that may also be contingent on who’s running that election year—and in 2016, Trump poses a conundrum for the Republican Party. “Party ID is very strong, but that depends on the candidate actually being clearly a Republican,” said Tammy Frisby, a fellow at the Hoover Institution at Stanford University. The nominee is expected to be the party’s standard-bearer, embodying its conservative values—even as they evolve.

“What ‘conservative’ meant in 1954 is not what ‘conservative’ means in 2016,” said Leah Wright Rigueur, an assistant professor of public policy at the Harvard Kennedy School of Government, pointing to when the religious right came into the party in the 1980s. Even so, various strains of conservatism have found a home in the Republican Party, Rigueur said. Trump is showcasing a type of conservatism that mainstream Republicans believed to be held at the fringes of the party and at odds with true conservatism, she added. And for some registered Republican voters, that has challenged how they identify with the party.

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.

“What you end up seeing, especially as Republicans are vulnerable in terms of their political reelection who have strong reservations about candidates from the mid-1960s and forward, you see them start to rally around candidates they had reservations about before. It’s party over everything,” Rigueur said, adding that Trump is pushing the boundaries of party loyalty by explicitly airing the differences between his brand of Republicanism and traditional Republicans. Then and now, voters don’t want to appear disloyal. But how they balance their identification to the party with their allegiance to it is pushing many to new limits.

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