Eva Gallagher carries cutouts of Republican presidential candidate Donald Trump while waiting in line outside a town hall meeting in Derry, N.H., on Wednesday. (Brian Snyder/Reuters)

They showed up by the hundreds. They stood in line under the hot sun for hours. They carried paper cutouts of Donald Trump’s face. They folded into the seats of a high school auditorium here, hard rock music pulsating, and got ready to ask questions of the bombastic billionaire they hope to elect president. This was Trump’s first New Hampshire town hall meeting, and the place was crackling.

A few minutes in, a man in the crowd shouted, “Isn’t Jeb sinking to the bottom of [Lake] Winnipesaukee by now?”

“Ahh,” Trump replied, “these are my people.”

Jeb Bush wasn’t at the bottom of any lake. He was 19 miles down the road from Derry, giving a workman-like performance before a sedate crowd of about 150 at a Veterans of Foreign Wars post in Merrimack.

Then Bush went on the attack. He fired his toughest shots to date at Trump, saying the businessman “doesn’t have a proven conservative record” because he is a former Democrat who once supported tax increases and a single-payer health-care system.

During a town hall meeting in New Hampshire, GOP presidential candidate Donald Trump slammed 2012 presidential nominee Mitt Romney, saying that he "choked." (Reuters)

In this first-in-the-nation primary state, tailor-made for a center-right, business-friendly, establishment-approved candidate, Bush is caught uncomfortably between the rising forces on his right and left. He has been unable to assert himself as the alpha candidate that many Republicans expected he would be.

The dynamic here reflects the extent of the broader tumult that has gripped the Republican race nationally, with 17 candidates vying for overlapping factions of the party. At the moment, the campaign is dominated by Trump and other political neophytes drawing enthusiastic crowds and preaching an anti-establishment message, though party strategists anticipate attention will shift to more traditional candidates eventually.

For now, at least, Bush faces a squeeze. Ohio Gov. John Kasich is moving swiftly to take advantage of the former Florida governor’s difficulties and make inroads with mainstream voters who otherwise would migrate to Bush.

Other candidates are trying to creep up, as well. New Jersey Gov. Chris Christie, fighting to gain traction here, parried questions at a tavern outside of Manchester. Wisconsin Gov. Scott Walker did the same in Barrington, while Carly Fiorina — the former Hewlett-Packard executive also rising in the polls — convened a give-and-take with voters in Laconia.

Trump has swooped in to galvanize many on the right here and nationally with his tough talk against political correctness and illegal immigration. Trump led the field in New Hampshire with 18 percent, followed by Bush at 13 percent and Kasich right behind at 12 percent, according to a recent Boston Herald/Franklin Pierce University poll of likely GOP primary voters.

Trump taunted Bush with his visit Wednesday. Only after Bush had announced his Merrimack town hall meeting did Trump schedule his for the same time in nearby Derry, inviting comparisons between their crowd sizes and performance levels.

As Trump’s capacity crowd grew restless — chanting “We want Trump!” — the candidate held court backstage for a half- hour with reporters. He slammed Bush for past comments about immigration, the Iraq war and women’s health. “I don’t see how he’s electable,” he said.

DES MOINES, IOWA - AUGUST 14: Republican presidential hopeful and former Florida Gov. Jeb Bush at the the Iowa State Fair on August 14, 2015 in Des Moines, Iowa. (Photos by Charles Ommanney/The Washington Post) (Charles Ommanney/The Washington Post)

He added: “Jeb Bush is a low-energy person. For him to get things done is hard.”

When Trump took the stage, he told the crowd: “You know what’s happening to Jeb’s crowd just down the street? They’re sleeping!”

The juxtaposition is not helpful for Bush, who, at a moment when voters want to feel electricity from their politicians, has been criticized for having no spark.

But what Bush lacks in populist bravado he makes up for in policy know-how. He deftly discussed the intricacies of education policy for 45 minutes at a forum in Londonderry, N.H., Wednesday morning. And at his town hall meeting in Merrimack, Bush went after Trump in response to a voter’s question.

“He was a Democrat longer in the last decade than he was a Republican,” Bush said. “Look, Mr. Trump has clearly got talent. . . . But when people look at his record, it is not a conservative record. Even on immigration where . . . the language is pretty vitriolic for sure, but hundreds of millions of dollars of costs to implement his plans is not a conservative plan.”

Still, Bush has failed to consolidate the center-right coalition that made up the base of support here for 2012 primary winner Mitt Romney. There has been no movement en masse toward Bush — especially among activists who have been in the trenches without him during President Obama-era political fights.

At an Elk’s Lodge in Salem, N.H., Wednesday, Kasich talked about his record of pragmatism in Congress and as governor as well as his compassion for the poor, the drug addicted and the mentally ill. The message voters came away with: He’s as experienced, practical and fit for office as Bush, but he’s the son of a mailman instead of a president.

“Trump doesn’t have a clue about government,” Alan Doak, an undecided Republican, said as he left Kasich’s event. “Bush and Kasich are the only ones with any real experience. And Bush has that name.”

Bush’s advisers and supporters say he has a “long-term” strategy designed to peak early next year and then carry him through a potentially long nominating contest.

“He’s not turning to Page 47 of his policy positions to check his answers,” said Jamie Burnett, a GOP operative here backing Bush. “He’s engaging people and giving them real answers.”

Right to Rise USA, the pro-Bush super PAC that raised more than $100 million, is set to begin airing millions of dollars worth of television advertisements in New Hampshire and other early voting states. The first ads are expected to be positive biographical portrayals of Bush’s eight years as Florida governor, which advisers believe will help show voters that he is his own man with his own record distinct from his brother and father.

A late entrant, Kasich is winning buzzed-about endorsements and has shot up in the polls here amid a multimillion-dollar ad campaign by his allied super PAC, New Day for America.

Over the past week, two important members of Romney’s New Hampshire team — senior adviser Tom Rath and former state House speaker Doug Scamman — have signed on with Kasich.

“People are thinking, ‘Enough dynasty politics,’ ” said Jeb Bradley, the state Senate majority leader and a former congressman. Another prominent Romney supporter in 2012, Bradley has not endorsed anyone yet. “People are looking for new faces.”

Like Bush, Kasich’s pitch to voters rests squarely on his record as a center-right conservative governor of a large battleground state. The Ohioan is accused of being overly brusque — during the Salem town hall, he repeatedly cut off verbose questioners — but his animated and unscripted style has resonated with voters averse to political doublespeak.

Pacing anxiously, Kasich told the crowd of about 100 that “I’m a conservative with conservative principles, but you just can’t do this alone.”

“I’m going to tell you what I think is practical and what I think we can get done,” he said as he discussed immigration reform.

Asked whether Bush’s struggles to consolidate the party establishment gave him an opening, Kasich told reporters, “If you think I’m going to answer that question, you’re nuts.”

Aides at Bush headquarters in Miami have been researching Kasich’s background, including the many votes he cast as a member of Congress, and are pitching reporters on negative stories about him. So-called opposition research is a staple of most campaigns, but it is telling that Kasich is now under the Bush team’s microscope.

Some major Bush donors quietly have reached out to the Kasich team in recent days to learn more about the Ohio governor and express interest in possibly supporting him, according to Republicans familiar with the conversations.

“Bush hasn’t done anything as a candidate, other than raise money, to indicate that he can concolidate mainstream Republicans,” said Andrew E. Smith, director of the University of New Hampshire Survey Center. “It means this is a free-for-all.”

Ed O’Keefe contributed to this report.