LAS VEGAS — Marco Rubio is keeping up the heat on Ted Cruz, suggesting he should fire someone for what he called a "pattern" of "deceptive and untrue" tactics and comments coming from Cruz's campaign.
But at the same time, he's continuing to avoid attacking the GOP front-runner, Donald Trump, even as he claims the fight for the nomination has narrowed to a three-man race.
Speaking to reporters before departing on his charter for a three-stop tour of Nevada on Monday, Rubio said with Cruz's campaign, "we're now at a point where we start asking about accountability. You talk about the VA, where people who aren't doing their job need to be fired —well, who's going to be fired when Ted Cruz is president? Because this campaign now has repeatedly done things that they have to apologize for and no one's ever held accountable."
His comments came in response to a video circulated by Cruz backers over the weekend that claimed — erroneously — to show Rubio telling Cruz's father, Rafael, and one of his staffers that there aren't many answers in the Bible. The chance encounter between Rubio and the Cruz contingency was caught on-film and someone incorrectly transcribed the interaction in on-screen text, and Cruz spokesman Rick Tyler posted it on his Facebook page.
Rubio told reporters that he had actually told the Cruz staffer that "the answer to every question you'll ever have is in that book - and then I pointed to the Book of Proverbs, which he was reading, I said, particularly that one, which is the book of wisdom."
"And then for them to take a video and to transcribe words on it that are the complete opposite of what I said — it's incredibly disturbing," he said.
The Cruz campaign ultimately chalked the video up to a misunderstanding, and Tyler apologized for it. Rubio said he accepted the apology but ticked off the recent controversies dogging Cruz over his campaign tactics — his staffers telling Iowa voters Ben Carson had dropped out; controversial robocalls allegedly coming from the senator's campaign in South Carolina and an ad attacking Rubio on cap and trade that South Carolina networks eventually took off-air because it misstated the facts — and said the latest video was part of a "very disturbing pattern of deceptive campaigns or flat-out just lying."
It's a continuation of an attack Rubio first launched in Iowa, where he accused Cruz of saying or doing anything to get elected, and ramped up in South Carolina after Cruz and Rubio each exchanged charges the other was lying at the last GOP debate.
Rubio's campaign kept up the scrutiny on Cruz through the weekend, issuing a call last Friday for their supporters to keep an eye out for "dirty tricks" from the Cruz campaign. And it wasn't just Rubio accusing Cruz of dishonesty — Donald Trump took up the charge as well, amplifying the message and contributing to a drop in Cruz's popularity over the past week that ultimately helped Rubio gain a slight edge over him in the South Carolina primary.
Rubio's second-place finish spurred Jeb Bush to drop out of the race, helping to consolidate the GOP primary into a largely three-man battle between Rubio, Cruz and Trump. But where Rubio hasn't shied away from attacking Cruz, he's been reluctant to take aim at Trump, avoiding every opportunity to criticize the front-runner — to the chagrin of some in the GOP.
On Monday, he again toed that cautious line. Asked if he agreed with a new ad from a super PAC supporting his bid that called Trump "erratic, unreliable," Rubio said he hadn't seen the ad and declined to comment on its substance. And while he raised doubts about his foreign policy understanding, Rubio still gave Trump the benefit of the doubt on that issue.
"I have said that when it comes to issues of national security, Donald has yet to prove that he has an in-depth understanding or the judgment to make good decisions about that — that could change," he said.
This story first appeared on NBCNews.com.