Sen. Ted Cruz (R-Tex.) at a campaign stop in Washington, N.H., on Monday. (Matt Rourke/Associated Press) (Matt Rourke/Associated Press)

Donald Trump says Ted Cruz is a “nasty guy.” The Texan’s Senate colleagues agree. Yet here’s the surprise from watching Cruz on the campaign trail: Ideology aside, he comes off as . . . rather likable.

To watch Trump and Cruz campaign here is to witness the difference between a reality TV performer and a disciplined politician. With apologies to the artists, Trump is Jackson Pollock to Cruz’s Rembrandt. One splatters paint with no coherent pattern, the other dabs with evident skill, albeit in notably dark tones.

Trump’s riff of a stump speech is all poll numbers (terrific) and crowd sizes (record), interspersed with millimeter-deep detours into policy. Common Core is terrible; the border wall will be great; he knows how to negotiate trade deals.

At one point at Concord High School on Monday, Trump paused when interrupted by a loud, high-pitched yelp. “What was that, was that a dog?” he asked. “Hillary,” an audience member shouted.

Republican residential candidate Ted Cruz tells supporters he's not interested in bashing his Republican rival, Donald Trump, and that Americans don't care for politicians "behaving like petulant children." (Reuters)

A more experienced politician — a more politically correct one, Trump would say — would have known to stand down. Not Trump. “Uh- oh, it’s Hillary,” Trump repeated, laughing and smiling. “Aaah,” shaking his head, “only in New Hampshire, huh?”

Still, Trump being Trump, he couldn’t let it rest. “First, it was a screechy dog, then it was a very serious dog, right?” he said. “Anyway, that’s all right. Take good care of your dogs.”

I’m not sure exactly what Trump meant — he probably didn’t know what he meant, except that to realize, belatedly, that he ought to back himself out of this line of non-thought, pronto. But there was nothing funny about the supporter’s shout, and nothing acceptable about Trump’s laugh-along response.

Cruz on the campaign trail has a set piece, a strict sonnet compared with Trumpian free verse. In New Hampshire, it begins with a well-placed geographic pander, one that also happens to involve Clinton.

“For the record, Tom Brady was framed,” he says, to inevitable cheers about the Patriots quarterback. “I’m not willing to pander on much” — laughter — “but on that, Tom Brady was framed, and I have it on good authority that Hillary Clinton was responsible.” More cheers. “Why else do you think she destroyed her emails?” This is not actually funny, but for New Hampshire Republicans, it amounts to a double-stuffed serving of red meat.

I knew before seeing Cruz on the stump that he is smart — dangerously so from my ideological perspective. I knew from watching him operate in Washington that he is ruthlessly ambitious. Seeing him in action, it’s clear he’s adept at retail politics as well.

Cruz knows how to connect with an audience; to soften people up with laugh lines and a smattering of scripture; to deliver his message with digestible details and a warning that aims at Trump without, for the most part, explicitly naming him: Judge candidates based on what they’ve actually done, not what they promise.

In one telling moment in Washington, N.H., a young mother of four challenged Cruz about whether he would provide paid family leave. His eventual answer boiled down to nothing: “Politicians love to campaign on giving away free stuff,” but, as with the minimum wage, market forces mean such intervention would hurt workers, not help them.

But he leavened this response with personal questions (How old? Boys or girls?) and, believe it or not, empathy: He knows about being the “baby brother with two older sisters”; he understands the “hard challenge” of juggling work and family. The woman may have left unconvinced, but Cruz’s deft response revealed a politician both skillful and relatable. The crowd applauded.

Because Trump and Cruz seem to be competing for the angry-outsider lane, I expected voters at Cruz events here to be torn between the two. Instead, I was struck by the still-undecided voters I met who had rejected Trump, using words like “antics” and “volatile” to describe him.

“The more I look at his record, the more I listen to what he’s saying, the less I’m likely to vote for him,” said Charles Wood, 45, a small-business owner from Weare. Added Gayle Terani, 71, of Washington, “When it comes to sitting across the table from global leaders, I don’t know if he has the patience or the demeanor.”

State polls have Trump firmly in the lead; New Hampshire, unlike Iowa, is not evident Cruz territory. But the Texan’s skill on the stump is undeniable. That he manages not to come off as a nasty guy makes him all the more dangerous.

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