Texas Sen. Ted Cruz and retired neurosurgeon Ben Carson both say Apple should help the FBI uncover encrypted data on a cellphone belonging to the San Bernardino attackers, while Florida Sen. Marco Rubio called Apple's refusal to meet the demand a complicated problem without a "magic solution."
The three Republican presidential candidates laid out their views in a televised town hall Wednesday night that pushed them to answer questions from voters, but because each appeared separately, the forum featured none of the sharp exchanges that have characterized the GOP debates during the 2016 election.
Rubio said the government and Apple needed to work together but admitted he did not have an easy answer.
"There has to be a way to deal with this issue," Rubio said. "I don't have a magic solution for it today … but I do know this: It will take a partnership between the technology industry and the government to solve this."
Cruz said, "Apple has a serious argument" in protecting users' privacy but said resisting the FBI's request for help amounted to defying a search warrant. Carson said that Apple should find a way to get over mistrust of the government, but then added that might have to wait until President Obama leaves office, allowing for a delay that the FBI would probably oppose.
CNN is holding the town hall over two evenings. Former Florida Gov. Jeb Bush, Ohio Gov. John Kasich and GOP front-runner Donald Trump, the business mogul and celebrity, were scheduled to appear Thursday night. Trump also held a simultaneous town hall on MSNBC Wednesday, doubling his exposure.
Even if they lack intensity, the town halls offer the last opportunity for many South Carolinians to watch the candidates field questions before the state's primary on Saturday. The candidates, feeling tremendous pressure to perform, have amplified their attacks on one another, with several slamming rivals as liars and other harsh terms.
Cruz used the platform to further press Trump and Rubio. Carson and Rubio took a different tack, telling more personal stories and trying to present their candidacy to voters who may still be seeing them for the first time.
Rubio, for example, shared his love of techno music, insisted he had never been to a rave and said he felt the sting of racism as a Cuban American growing up in Las Vegas during the Mariel boatlift in 1980, when tens of thousands of Cubans left for Miami in 1980.
"Some of the kids, the older kids, were taunting my family: 'Why don't you go back on your boat?'" Rubio recalled. "I said, 'What boat? My mom doesn't even swim.'"
Cruz and Rubio have been battling for second place in South Carolina polls and both see a strong finish as crucial in their effort to emerge as Trump's chief rival. If Rubio finishes poorly here, he will have significant difficulty remaining viable in the race.
Rubio got a boost Wednesday with the endorsement of Nikki Haley, South Carolina's popular governor. He tried to capitalize on that endorsement, and the backing of Sen. Tim Scott of South Carolina, by framing them as part of his broader message that he is a new generation Republican.
"Today I got the endorsement of a governor of Indian descent who endorsed a presidential candidate of Cuban descent, and tomorrow we'll be campaigning alongside an African American Republican senator," he said.
He also highlighted proposals aimed at reducing college costs and offering higher child tax credits, policy issues aimed at reinforcing his argument that he would make a better general-election candidate than his GOP opponents.
Cruz shared some of his personality, even singing a few bars of "I Just Called to Say I Love You," which he said he sings to his wife, Heidi, on the phone. But he mostly showed a harder edge as he battled to both fight off Rubio for second place and try to catch Trump, who is leading statewide polls.
Cruz insisted that he was not attacking Trump and Rubio personally, but spent much of his time discussing Trump's past support for liberal policies such as abortion rights and Rubio's record advocating for a path to citizenship for immigrants in this country illegally.
He said both men were labeling him a liar to distract from their records.
"Marco followed the same strategy as Donald. He just screamed 'liar, liar, liar,'" Cruz said. "Truth matters."
Cruz also highlighted his record as Texas solicitor general, when he argued conservative positions before the U.S. Supreme Court, to make the case that he was the only one in the field who could be trusted to select a true conservative to replace Justice Antonin Scalia, who died Saturday.
Cruz, like other candidates, has said Obama should not nominate a replacement during an election year. He introduced a new argument Wednesday to make the case that the Senate should not even conduct hearings until a successor to Obama is elected.
"That hearing would end up very politicized and it would not be fair to the nominee," he said.
Carson conceded that if he were in Obama's place, he too would nominate a replacement for Scalia. But, he added, that doesn't necessarily mean Congress would confirm that pick.
Carson, once popular among evangelical voters, has faded in polls. He tried to broaden his appeal as a "citizen statesman" who bases his beliefs on both the Constitution and the Bible, a nod to the power of religious conservatives in South Carolina primaries.
Trump, appearing on MSNBC, said he would not appoint anyone to the Supreme Court unless the nominee agreed to uphold a landmark 2008 ruling that recognized the right to bear arms.
Even as he tried to reinforce his credentials as a conservative, Trump boasted he would win over Democrats in a general election.
"If I get the nomination, I will have more cross-over votes than anybody that's ever run for office," Trump said.
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Times staff writers Lisa Mascaro in Columbia, S.C.; Seema Mehta in Charleston, S.C.,; and Michael Finnegan in Las Vegas contributed to this report.