There’s a standard operating procedure for presidential candidates in New Hampshire: you pick a business, chat up the locals, give a speech, and then meet the press. But Thursday in Portsmouth, Rand Paul took a different tack.

At the bakery Popovers on the Square—the last stop of Paul’s three-day Granite State swing—the Kentucky Senator spent plenty of time shaking hands, posing for photos with his fans, and even giving career advice. He did it all in a relatively quiet voice, with a minimum of excess movement.

“What do you want to be when you grow up?” Paul asked a young boy, who shyly replied: “A congressman.”

“Oh, that’s good,” Paul answered. Then, cupping his hand next to his mouth and speaking in a mock-conspiratorial stage whisper, he added: “But be something good first—be like a doctor, or an engineer, or a computer software person. Make something. Discover good things, so we can have progress.”

“Then, when you’re done discovering good things, then do something like go to Congress,” Paul added. “All right? Good deal.”

But then, after he’d worked the room for several minutes, Paul simply…left. There were no prepared remarks. And he didn’t stop to take questions from the press.

Paul’s diffidence was especially striking given how aggressive he’s been recently with Donald Trump, the GOP frontrunner.

In last week’s Fox News debate, Paul went after Trump hard, saying he “buys and sells politicians of all stripes.” And yesterday, Paul rolled out an ad purporting to out Trump as a closet liberal—highlighting his past support for Democratic policies and candidates, including (gasp!) Hillary Clinton.

Naturally, the media covering Paul in Portsmouth today wanted to ask him about his escalating feud with Trump. So as he walked down Congress Street toward his truck, a pack of journalists chased him a short distance.

When he stopped, I was able to get one question in: what’s the response to the new ad been, from primary voters and, perhaps, Paul’s Republican rivals?

 “I think there’s a lot of voters who are eventually gonna ask themselves some tough questions, and those are, is Trump really a conservative, or is this all a put-on or a show or an act?,” Paul replied. “And I think it is an important question, because most of Donald Trump’s life has been as a progressive Democrat. And that’s fine—but when someone has a late-life conversion, you wonder whether it’s real or it’s an act.

“The Tea Party movement that I came out of is a movement where we were unhappy with people who were fake conservatives—people who said, ‘Oh, we’re for limiting government,’ and then they got in and made government bigger,” he continued. “So people have to ask: Donald Trump was for Obamacare before he was against it. He was a Democrat before he was a Republican. He’s for a single-payer system, universal healthcare. He calls himself a liberal on healthcare. So the question is, is there a sincerity?”

Of course, there’s been strange dynamic in this campaign: when you think something’s going to hurt Donald Trump, it helps him instead. So the question now is, will Paul’s attacks work? Or will they backfire?

One Paul supporter I spoke with said he’s concerned that, by taking on Trump, Paul will restrict his own ability to make the case for his own candidacy.

“Sometimes if you go after another candidate, it doesn’t work out as well for you,” said Joe Crepeau of York, Maine. “And you know Trump’s gonna come back with something too, so it’s gonna be back and forth, back and forth. And that might take away from the message that Rand Paul’s trying to get out there.”

Naturally, I wanted to ask the candidate himself about that possibility. But today in Portsmouth, that wasn’t possible. After answering that one question, Paul turned away from the media gaggle, walked up Congress Street to his truck, got in, and drove away.