"No more Viagra!" a man hollered.
"Shout that out once more," Trump responded with a grin.
"No more Viagra!"
The Republican presidential candidate opened his arms wide as laughter spread. "I didn't say it," he deadpanned. "Do they make Viagra? Is it Pfizer? … This guy's a comedian."
So is Trump, whose political rallies often resemble stand-up comedy shows. Funny, engaging, insulting, cocky and vulgar, the former reality television star remains a showman at heart as he campaigns for president.
Back-and-forth banter with fans, as Trump calls them, is a staple of the act. It looks spontaneous; it's anything but.
"The misconception is that this is just stream of consciousness," said Corey Lewandowski, Trump's campaign manager. "It's not. It is thought out. It's strategic. It is precise. It is controlled."
Trump's keen sense of his audience has, for better or worse, made him the dominant force in the 2016 election. It's less his agenda, provocative as it is, than his mastery of the stage that has set him apart from rivals in the race for the party nomination.
Only Trump could expect to get away with skipping Thursday's Fox News debate in Des Moines and staging his own simultaneous event on the other side of town just four days before the Iowa caucuses. Politics is always theater, but never quite like this.
At his rallies, Trump performs like a professional comedian who has memorized a menu of exhaustively rehearsed jokes. He sticks with a few dozen routines, adjusting them to suit his political needs of the moment. The delivery can vary, but his riffs are punctuated by frequent laughs; his punch lines hit more often than they miss.
Trump's themes are straightforward — stop illegal immigration, build up the military and promote job growth with a more combative posture on trade.
He has framed his candidacy with a rationale so simple that it's impossible to leave a Trump event without getting the point: America's greatness must be restored by a strong leader who is not beholden to campaign donors.
Trump's call to build a wall along the country's southern border is a high point at many rallies.
"Who's going to pay for the wall?" he asked supporters Sunday at Central College here in Pella, a Dutch-themed town known for its namesake window manufacturer.
"Mexico!" the crowd answered. Awash in cheers, Trump flashed a thumbs-up, then spread his arms. "Mexico. Hundred percent."
He pivoted to a joke about environmental rules keeping the U.S. from building the wall decades ago. "There were snakes in the way," he said, drawing chuckles from the crowd. "Or there were toads in the way. Or there was something else. A frog. A mosquito."
Trump's conversational style, animated with hand gestures, is that of a chatty cab driver from his native Queens. Men are "fellas" and "wiseguys."
His most potent comic device is the insult. With a deft touch, Trump's put-downs have all but destroyed rival Jeb Bush, said David Doak, a veteran campaign ad maker.
"Ridiculing somebody is an even more effective way to hurt them than just being nasty toward them," said Doak, a Democrat. Trump's mainly white, blue-collar backers are especially susceptible to humor that skewers a wealthy political dynasty, he said.
The pokes at Bush and his "Jeb!" campaign slogan are among Trump's biggest applause lines.
"The guy's ashamed to use his last name," Trump told the Pella crowd. "I said, 'Get rid of the exclamation point, Jeb, and use Bush. It's OK. Everyone knows you're Bush. Don't be ashamed. Be proud, Jeb.'"
Trump likes to mock a TV ad featuring Bush's mother. "I said, 'Jeb, you cannot have your mother negotiate with ISIS,'" he says to a burst of laughter. "'You have to do it yourself.'"
Hank Sheinkopf, a New York campaign consultant and Democrat, compared Trump's rallies to revival meetings where the candidate plays "slayer of the elites" for a crowd that agrees the game is rigged against Americans struggling to get by.
"He's the 21st century Don Rickles of American politics, because he's not just making jokes, he's sticking it to his opponents," said Sheinkopf, referring to the 89-year-old New York insult comic.
News media are a favorite target. Some days, they are "bloodsuckers"; other days, "scum." A popular punch line is bow-tied conservative pundit George Will, who once wrote of Trump's "comprehensive unpleasantness."
"Take away the glasses, he looks like a dumb guy," Trump told supporters in Ames, Iowa, last week.
In Iowa, where his chief rival is Ted Cruz, Trump skewers the senator from Texas at every stop over his Canadian birth to an American mother. By Trump's telling, that could disqualify Cruz from the presidency.
"Ted Cruz will approve the Keystone pipeline because it benefits Canada," he told a crowd this week in Muscatine, referring to the proposed oil line between Alberta and Texas. "Great. He could be the only guy who could run for president, and then run for prime minister of Canada."
Trump's liberal use of vulgarity has lost its shock value. Even as he was playing up his Presbyterian heritage in strongly evangelical regions of Iowa last weekend, he won applause for calling opponents' advertising a more descriptive version of "total bull."
To Chip Felkel, a Republican consultant in South Carolina, Trump's freewheeling vitriol reflects an "unhealthy and unsettling mind-set" in America. But where some see a bully, others see a protector, he said.
"The anger is visceral, the frustration is over the top, and Trump is a master showman at playing to that," he said.
Shelly Larson, 53, a Republican office worker at a Pella construction equipment maker, said Trump's crudeness makes her trust him more. "The country's in a downward spiral," she said as she left the college auditorium. Trump's was the first political rally she'd ever attended.
Facing skepticism over his temperament, Trump has vowed to tone down his rhetoric should he win the presidency. "I can be the most politically correct person that you've ever seen," he said in Pella. "I could leave a dinner and everyone would say, 'What a fine, outstanding man.'"
Trump prides himself on keeping spectators engaged. "Isn't a Trump rally more fun than all these other stiffs?" he asked one crowd in South Carolina. "You go to Jeb Bush's rally, you fall asleep almost immediately."
At the New Hampshire high school, he singled out audience members as he argued that more people should carry guns to minimize casualties in terrorist attacks like the recent ones in Paris and San Bernardino.
"Mr. Viagra over here," Trump said to a ripple of laughs, "if he would have had a gun strapped to his ankle or his waist — and if you, and you, and a few of you would have had a few guns — it would have been a whole different story, folks."
With that, he opened his arms wide once again.