Donald Trump and Texas Sen. Ted Cruz continued to joust for primacy heading into the South Carolina primary next weekend, foregoing policy differences for name-calling and insults.
Trump called Cruz "nuts," "dishonest" and "an unstable person," while Cruz questioned both Trump's conservative credentials and whether he had the temperament to be president. Cruz is trying to weaken Trump's standing among South Carolina's social conservatives and evangelical Christians, a key voting bloc in Saturday's contest.
"The people of South Carolina want a consistent conservative they can trust," Cruz told reporters before his rally in Aiken.
About the same time at a rally 130 miles away in Mount Pleasant, Trump called Cruz "the most dishonest guy I think I've ever met in politics."
"I think he's an unstable person," he said, later declaring: "He's nuts"
Speaking to hundreds of supporters, Cruz said he intends to make the presidential race a referendum on the Supreme Court and the importance of electing a president who will nominate conservatives. The issue is at the forefront of the presidential race following the sudden death of conservative Justice Antonin Scalia, whom Cruz praised as a "lion of the law."
Cruz said before his rally that a vote for Trump would be a vote for doing away with Second Amendment gun rights, predicting that the billionaire businessman would appoint liberal justices to the Supreme Court. He ticked off a list of Democrats Trump had donated to in the past, including 2004 presidential nominee John Kerry.
Cruz also took issue with Trump and Florida Sen. Marco Rubio. Both called him a liar during Saturday's debate. Cruz said they both "simply scream 'Liar, liar!'" whenever their records are questioned, and that approach would not work when negotiating with the likes of Russian President Vladimir Putin.
Cruz also blasted Trump's apparent confusion during a Republican debate last year over what constituted the nuclear triad as an example of how the real estate mogul is unprepared to be president. And Cruz again returned to criticizing Trump's praise of Planned Parenthood.
Cruz released a television ad on Sunday attacking Trump for previously saying Planned Parenthood "serves a good function." In Saturday's debate Trump said that the organization "does do wonderful things, but not as it relates to abortion."
"He's entitled to have that opinion," Cruz said Monday. "A lot of liberal Democrats have that opinion."
Cruz also said Rubio's positions on supporting a path to citizenship puts him in line with "a lot of liberal Democrats" including Hillary Clinton. Rubio has previously supported a path to citizenship for people in the country illegally, but has backed off that position and now says border security must be increased first.
Even as Cruz sharpened his attacks on Rubio and Trump, he said the campaign "shouldn't just be about insults and personal attacks."