CORAL GABLES, FL — (CNN) He’s got the deepest pockets, the best organization and everyone already knows his name.

But Jeb Bush isn’t so formidable that he’s scaring away the competition.

When the former Florida governor formally announces his presidential campaign on Monday, he will join a field of 10 GOP contenders — and there are still a handful of others who may soon jump in the race. Meanwhile, the latest Iowa polls show him trapped in a cluster of candidates vying for second behind Wisconsin Gov. Scott Walker, and he has only a slight edge in New Hampshire. National polls show Bush a touch ahead, according to a Real Clear Politics average.

For all of his advantages heading into the race, the man with the famous last name who many assumed would be an automatic frontrunner is struggling to catch fire.

“Frankly, I thought that Jeb was going to just suck all the air out of the room and it just hasn’t happened,” said Ohio Gov. John Kasich recently. Kasich is toying with a presidential bid that will hinge largely on New Hampshire.

Bush has struggled under the weight of high expectations, but also the changing nature of campaigns.

“He’s stumbled a little bit,” said Katie Packer Gage, a Washington-based GOP strategist who was Mitt Romney’s deputy campaign manager in 2012. “I think that has emboldened a lot of these candidates.”

Bush’s representatives insist they aren’t surprised by Bush’s standing and expect him to fight hard for the nomination.

“It’s June for crying out loud, so we’ve got a long way to go,” Bush told reporters in Germany on Wednesday, as he fielded questions about his team’s performance so far. “I’m pretty confident that we’re in a good position, for sure, and I’m going to compete everywhere. If I’m a candidate there’s no fifth place kind of mentality.”

Still, there are signs that Bush’s early campaigning hasn’t gone as smoothly as he had hoped.

He stumbled badly last month when faced with questions about his thoughts on his brother’s invasion of Iraq, an inquiry many Republicans said he should have been prepared for. The shaky responses left an impression that Bush, who hasn’t run for public office in more than a decade, is a rusty campaigner.

Bush could face new turbulence after the Huffington Post on Tuesday published excerpts of a book he wrote in 1995 in which he laments changes in society that reduced the stigma associated with unwed mothers.

Bush is shaking up his campaign team just ahead of his announcement date. Communications specialist Danny Diaz will become the campaign’s manager, a surprise to many who had expected David Kochel, a veteran Iowa operative, to fill the role. Kochel will stay on as chief strategist.

Meanwhile, a shifting landscape in how candidates can raise money — and how they can spend it most effectively — is also creating a more crowded field. Since super PACs can accept unlimited donations, it’s easier for candidates’ allies to keep them afloat even if they are outraised. And digital advertising offers campaigns and outside groups a cheaper and more targeted method of reaching voters than pricey television ads.

“Now candidates that don’t have as much money aren’t just overpowered anymore by candidates who can spend a ridiculous amount on TV,” said John Brabender, a senior strategist for former Pennsylvania Sen. Rick Santorum’s 2016 presidential campaign.

Few understand how far a few million can go like Santorum’s camp, which eked out a surprise victory in Iowa in 2012, and created headaches for Mitt Romney until April of 2012, when Santorum eventually suspended his campaign. Santorum’s primary financial backer, wealthy conservative donor Foster Friess, has signed on to support him again in 2016.

“Frankly in 2012, we had a very weak field of opponents,” said Packer Gage. “We still almost lost.”

Still, Santorum’s top strategist said Bush is facing unrealistic expectations so early in the presidential campaign cycle.

“There was a perception that, oh, he’s a Bush, and he should be way out in front. I think that’s unfair even to him, I would argue,” Brabender said. “That’s not how Republican primary voters operate.”

Voters in Iowa have been particularly loath to embrace establishment frontrunners, instead leaning toward candidates like Santorum or former Arkansas Gov. Mike Huckabee, who won the caucuses in 2008.

This campaign cycle presents another new hurdle: It’s unclear what event could winnow the field early on.

In the past, some candidates who performed poorly in the Iowa Straw Poll quickly withdrew from the race. This year, none of the candidates have committed to participating in the event. Bush, Huckabee, Florida Sen. Marco Rubio and South Carolina Sen. Lindsey Graham all plan to skip the beauty contest, which does not yield delegates that help candidates win the nomination.

Team Jeb, meanwhile, is still focused on a fundraising blitz so it can unveil an eye-popping sum. After pressing donors to raise money for his leadership PAC and his super PAC, his staff is shifting into official campaign mode and hitting up donors yet again.

A fundraising packet from Heather Larrison, who will be the campaign’s finance director, encourages bundlers to raise $27,000 in the 15 days between Bush’s official announcement June 15 and the end of the month, when the campaign will have to file its fundraising totals. Donors who meet the goal will be rewarded with a picnic with Bush “and special guests,” in Kennebunkport, Maine, and a campaign briefing in early July, according to the packet.

“I don’t think that Jeb is frankly going to ever scare all of these folks out,” said Douglas Gross, an Iowa Republican who is not affiliated with a campaign. But he pointed out that candidates taking on Bush have not yet felt the impact of tens of millions of dollars of attack ads either.

Bush’s war chest, “hasn’t forced them out of the race because he hasn’t used it yet,” Gross said. “We’ll see how they do once the bombing starts.”

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