If there’s one thing that characterizes Sen. Ted Cruz, it’s discipline — it’s exceedingly rare to hear him utter a word out of place. But rival presidential campaigns, and even a key Cruz ally, believe he tripped up by uttering the phrase that’s followed him all week: “New York values.”

Cruz attached the phrase to Donald Trump earlier this week and it carried it into Thursday night’s sixth Republican presidential debate, where he was pushed to explain just what “New York values” mean. His definition: “socially liberal, pro-abortion, pro-gay marriage and focus around money and the media.”

That gave Trump a Lincoln Tunnel-sized opening and he took full advantage of it, abandoning his usual insult-comic style for a movingly earnest tribute to his city’s courage in the face of the 9/11 terrorist attacks. Even Cruz clapped along during his response.

“No place on Earth could have handled that more beautifully, more humanely than New York,” Trump said.

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How well did that sound bite play? Congressman Steve King, Cruz’s national co-chair and a legend in his own right when it comes to divisive rhetoric, sighed on CNN that his candidate had picked the wrong fight, even if invoking 9/11 was “below the belt.”

“I didn’t think he went too far until I saw Donald Trump’s reaction,” King said. “Then I thought it would have been better on the part of Ted Cruz not to have had that exchange.”

Rival campaigns were happy to join the pile-on. Even Hillary Clinton, who represented New York as a senator, tweeted, “Just this once, Trump’s right.”

Mike DuHaime, a top strategist to New Jersey Gov. Chris Christie, made the case to MSNBC on Thursday that Cruz undermined his electability argument by pitting states against each other.

“We shouldn’t do that, it’s not helpful, and it signals why we as a party have lost ground in general elections,” he said.

Trump’s South Carolina campaign chair Ed McMullen predicted that the attack would fall flat even for its intended audience in the state, where there’s been significant population growth driven by northeast transplants.

“We have a lot of in-migration from all over the country,” he said. “This is not your 1970s South Carolina. It’s a very different South Carolina.”

Critics of Cruz’s approach also pointed out that he left fertile ground for attack on hypocrisy grounds. Sen. Marco Rubio in particular has tried to portray Cruz as a panderer rather than the most pure conservative in the race, and Cruz’s fundraising in New York (including a reception at the home of a married gay couple) and his wife’s work for Goldman Sachs, which also provided a seven-figure loan during his Senate campaign, could provide ammo for his case.

At the same time, Cruz’s campaign can make a compelling pitch that the “New York values” fight is a net positive despite Thursday night’s negative reviews.

Cruz’s campaign aides pointed out the obvious after the debate: The supposed backlash over “New York values” likely looks a lot more widespread than it is because the national news media is concentrated in New York. Fox Business host Maria Bartiromo, who moderated the debate, even mentioned her New York roots in her question to Cruz on the topic.

“I understand why the New York media defends New York — that’s fine, I love New York,” Cruz spokesman Rick Tyler told reporters on Thursday. “They are a little sensitive.”

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Then there’s the question of what Cruz’s goals are in litigating the New York attack. Right now, Cruz’s most important strength is that he’s largely consolidated the social conservative vote in Iowa, which is critical to turning his narrow polling lead over Trump into success in the Feb. 1 caucus. He needs to keep Trump, who tends to draw support more easily from less religious and less ideological voters, from eating into his base at all costs. Starting a fight over abortion, marriage for same-sex couples, and secularism hardly seems like a crazy defensive play in that context.

view photo essay The presidential campaign: Ted Cruz The Texas senator was first to announce his bid back in March, and has since been carefully laying the groundwork for a come-from-behind primary victory.

The question for Cruz is whether Trump is vulnerable to attack given that plenty of other campaigns have tried to go after him on similar grounds, minus the regionalism, with little success. The billionaire has hardly made a secret of his background; he’s a walking parody of a brash New Yorker. Nor has he pitched himself as particularly pious either: He once told a conference of Iowa social conservatives that he doesn’t like to pray to God for forgiveness. Voters have had plenty of time, and not just during the presidential campaign, to absorb these aspects of his personality.

Cruz appears to be betting that his credibility with movement conservatives will give the same attacks more sting than past Trump critics. His strength in the polls means they won’t have the same air of desperation that, say, Rick Perry or Bobby Jindal suffered from when they pivoted hard against Trump.

So far, betting against Cruz’s political instincts hasn’t paid off for anyone in the race. On that basis alone, it’s worth waiting before leaping to conclusions after the latest round of criticism.