BEAUFORT, S.C. (AP) — Ted Cruz is getting hammered by his Republican rivals over what they call a pattern of unethical campaign tactics and inaccurate statements by the Texas senator who has shaped his White House bid around trust.

Cruz has had some trouble getting all his facts straight in debates, has used campaign tactics that some find suspicious and had an ad by an outside group temporarily pulled for questions about its accuracy. His opponents are blunter, calling him simply a liar.

The Texas senator shrugged off the criticism Tuesday while campaigning for Saturday’s South Carolina Republican primary.

“Both Donald Trump and Marco Rubio have this very strange pattern where if you point to their actual record, if you point to the words that have come out of their mouth, they don’t respond on substance. They just scream ‘Liar! Liar! Liar!'” Cruz said Tuesday.

Both Trump and Rubio have accused Cruz of distorting their records with increasing frequency. And while such charges are common in presidential politics, Cruz’s team has also faced rebukes for misleading voters in recent weeks from multiple outside groups – the Iowa Secretary of State and a prominent anti-abortion group, among them.

The fiery conservative’s ability to navigate questions about his integrity could well decide his fate in the crowded 2016 contest, where he remains a top-tier contender.

“He’s lying. And I think it’s disturbing,” Rubio said in Beaufort. “Just here in South Carolina this week, he’s lied about my record on Planned Parenthood, he’s lied about my position on marriage, he’s lied about his own record on immigration. So, I think this is very disturbing when you have a candidate that now on a regular basis just makes things up.”

Trump was even more aggressive, describing Cruz the day before as “the single biggest liar I’ve ever come across, in politics or otherwise.”

“And I have seen some of the best of them,” the billionaire businessman said in a statement. “His statements are totally untrue and completely outrageous. It is hard to believe a person who proclaims to be a Christian could be so dishonest and lie so much.”

Virtually all of the 2016 candidates have been caught stretching the truth over the course of the campaign, including Trump and Rubio. But only Cruz has embraced trust – and the play on his first name, “TRUSTED,” as the fundamental rationale of his campaign.

After a legal review, a South Carolina television station over the weekend pulled down an ad from a pro-Cruz super PAC that targeted Rubio’s position on immigration. Among other charges, the ad said Rubio worked to allow “sanctuary cities” as part of the immigration deal he struck in 2013. Although the ad is running again, the station had questioned whether the charge was misleading.

The Cruz campaign, which is barred from legally coordinating with the super PAC, claimed no knowledge of the ad. Yet Cruz continues to face fallout from at least two incidents leading up to his victory in Iowa’s Feb. 1 caucuses.

As Iowa voting began, Cruz supporters incorrectly spread word that rival Ben Carson was leaving the race. That was just days after the Iowa Secretary of State condemned Cruz campaign for sending bogus notices warning of election “violations” to Iowa voters to persuade them to participate in the caucuses.

Iowa’s secretary of state criticized the tactic “as not in keeping with the spirit of the Iowa caucuses.”

Late last week, Cruz was also chastised by the anti-abortion group, National Right to Life, for accusing Rubio of not fighting to strip federal funding from Planned Parenthood. The organization called Cruz’s attack “inaccurate and misleading.”

And on immigration, Cruz in recent weeks has repeatedly overstated the deportation records of past administrations and misstated his own position on the 2013 so-called “Gang of Eight” legislation. The senator publicly backed legislation that proposed eventual legal status for millions, while stopping short of offering them a path to citizenship.

While polls indicate Cruz’s favorability is falling, his loyalists seem unperturbed.

“I trust Cruz 100 percent,” said 67-year-old Dick Winters, a retired Navy veteran from Charleston. “They’re taking things he’s done and twisted them around.”

It was much the same at a Rubio rally 90 miles down the South Carolina coast, where Carol Benz, a 54-year-old Republican from nearby Port Royal, said her confidence in Cruz was based on a series of actions over time, not a single event on the campaign trail.

“Do I trust him? Yes I do,” Benz said of Cruz, citing his fight against the federal health-care overhaul that triggered a government shutdown. “He didn’t back down.”

But Trump supporter Tom Kennemore said he appreciates the brash businessman’s willingness to tell the truth no matter what.

“I’m leaning away from Cruz,” Kennemore said at a Trump rally in Greenville Monday night. “I’m glad Trump pointed out his dishonesty.”