Nearly 27 years after his father was elected president, moulding a political dynasty that would propel one son into a governor's office and another into the White House, Jeb Bush was preparing to declare his own bid for the presidency in Miami last night.

But Bush will enter a presidential contest – unruly in size, unyielding in pace and voracious in cost – unlike any faced by his father, George Bush, who won the office in 1988, or his brother, George W Bush, who claimed it in 2000.

And as the third member of his family to seek the nation’s highest office, he brings to the race a last name that at once burnishes and tarnishes, evoking the nobility of public service and a deep distrust of political entitlement.

His campaign will highlight that tension with the selection of a spare logo, first used in his failed 1994 race for governor, that excludes his surname. It reads simply “Jeb!” And while Bush’s wife, Columba, and his three adult children planned to attend his speech, aides said his father and brother would not join him for the announcement at the Kendall Campus of Miami Dade College.

Fundraising prowess

Bush’s advisers and allies once predicted that he would emerge as the dominant Republican in the 2016 campaign, fuelled by his record of conservative accomplishment as Florida’s governor, his popularity at the end of his time in office and the fundraising prowess of the Bush family network.

But now they are resigned to a far longer and uglier slog for him in the Republican nomination contest. "The operative word inside the campaign is patience," said Al Cardenas, a former Florida Republican Party leader and ally of Bush. "As people get to know him, things will get better."

Bush made his announcement in the multicultural city that allowed him to escape from his family's patrician roots in the ivy-covered walls of Connecticut and in the oil patches of Texas. It was Miami that eventually nurtured the political ambitions that had long been a birthright of his clan.

In his speech, he was expected to both embrace elements of his heritage and try to transcend them, portraying himself as an entrepreneurial figure who, in the Bush family way, struck out on his own, built up a real estate business and became a governor who delivered a promise of sweeping change.

“I said I was going to do these things, and I did them,” Bush declared in a video released by his political operation on Sunday night. “The result was Florida’s a lot better off.”

Crowded field

Joining a field crowded with governors and senators, he will try to distinguish himself as an executive animated by big ideas and uniquely capable of carrying them out, pointing to his record in Florida of introducing a taxpayer-financed school voucher programme, expanding charter schools, reducing the size of state government by thousands of workers and cutting taxes by billions.

Above all, he will offer himself as a messenger of optimistic conservatism, uninterested in the politics of grievance, obstructionism and partisanship that, in his eyes and those of his allies, have catapulted less accomplished rivals, such as senators Ted Cruz of Texas and Rand Paul of Kentucky, to national prominence.

Leadership, he says in the video, is “not just about yapping about things”, an unmistakable attack on his voluble, less seasoned rivals from the Senate. He adds: “There’s a lot of people talking. And they’re pretty good at it. But we need to start fixing things.”

The risk for Bush, a cerebral figure who seems more at ease debating the intricacies of education policy with business leaders than electrifying a crowd of voters, is that the charismatic talkers in his party may outshine him before ballots are cast. He has yet to emerge as a front-runner in polls, lagging rivals in crucial states such as Iowa, which will hold its caucuses early next year. Cardenas said yesterday's speech was only the beginning of a long sales pitch that Bush must make in states with early nominating contests such as Iowa and New Hampshire.

“I consider the early states an asset for most candidates who are introducing themselves, and a burden for Governor Bush,” Cardenas said. “The reason for that is that since 2006, many of our pundits in the party have not been kind to the Bush family.”

Many Republican-elected officials who admire Bush have nevertheless held back from endorsing him, saying he still needs to prove himself.

Jeb Bradley, the majority leader in the New Hampshire State Senate, said Bush met his three criteria for an endorsement – leadership skills, appealing stances on most issues and ability to win – but that he was still open to backing two other Republicans, Senator Marco Rubio of Florida and Governor Scott Walker of Wisconsin.

Town-hall meeting

“I want to see what Governor Bush says in [yesterday’s] speech, see him at a town-hall meeting up here, see what his fundraising looks like,” Bradley said.

The announcement of Bush’s White House run ended an unusual, legally problematic and occasionally comical phase in which he travelled, raised money and campaigned as a full-fledged candidate but insisted, despite all evidence, that he was not officially exploring a presidential run.

It was a claim that allowed Bush to collect vast sums of cash for the political entities that could supercharge his campaign, but it produced several moments of semantic gymnastics. Despite Bush’s stumbles so far, his friends and allies said his biggest asset was his unwillingness to transform himself into something he is not.

"I think he needs to put aside the last few months and continue to calmly show a grown-up attitude," said Barry Wynn, a prominent South Carolina Republican and donor. "The two things that will distinguish him are his stature, that he is a grown-up ready for the presidency, and his consistency, that he's not changing to make everyone happy."

“The worst thing for Jeb to do is give his opponents any opportunity to close the stature gap he enjoys.”

But it remains unclear whether conservative-leaning voters will be as animated by Bush’s “grown-up” qualities as the party’s donor class, which has formed his core of early support. “I am going to be who I am,” he said in Europe last weekend, on a trip during which he barely interacted with ordinary people. “I’m not going to change who I am,” Bush said as he left the meeting, his last in Europe, and headed home.

–(New York Times service)