Bush, 61, said on Tuesday he will establish a political action committee in January, a step that an aide said will allow him to engage politically with supporters and potential donors and determine whether sufficient support exists for a run.

To be successful, Bush will have to overcome opposition from increasingly powerful conservatives in the Republican Party in order to best what is expected to be a crowded Republican field in 2016.

He will also have to gauge whether Americans would support another president named Bush. He is the son of former President George H.W. Bush and the brother of former President George W. Bush. He served as Florida's governor between 1999 and 2007.

By jumping in early, Bush puts potential competitors such as New Jersey Gov. Chris Christie, former Massachusetts Gov. Mitt Romney and Kentucky Senator Rand Paul on notice that they would have to get past him to win the nomination.

A source close to the Bush team said the accelerated timeline reflects the former Florida governor's wish not "to be left in the dust."

"It's extremely clever because he will be the talk of holiday tables all across the country," said Saul Anuzis, a former chairman of the Michigan Republican Party. "By coming out early, he establishes the bar for everybody else to meet and immediately ties up a tremendous amount of the financial community."

A Bush candidacy could set up a classic clash of two American political dynasties.

Former Secretary of State Hillary Clinton, wife of former President Bill Clinton, is the early favorite to be the Democratic presidential nominee in 2016, creating the possibility of a Bush-Clinton rematch of the 1992 election between Bill Clinton and George H.W. Bush, won by Clinton.

A final decision on whether Bush will seek the Republican presidential nomination will come at some point next year after he travels to key states and talks to voters.

"In the coming months, I hope to visit with many of you and have a conversation about restoring the promise of America," Bush wrote.

FAMILY CONCERNS

Bush had shied away from running for president out of respect for family considerations. He appears to have settled any concerns that his wife Columba has about his re-entering the political fray. In a Facebook posting, Bush said he had discussed the country's future with his family.

A new Washington Post-ABC News poll of Republicans and Republican-leaning independents released Tuesday shows Bush running first in a Republican field without Romney, though not leading by a statistically significant margin. He gets 15 percent, compared to 11 percent for both Paul and Representative Paul Ryan of Wisconsin.

In a field with Romney, Romney leads Bush 20-10 percent, with Paul at 9 percent and Ryan at 8 percent.

Bush will likely face resistance from conservatives for his moderate positions on immigration reform and education policy. Bush, who is fluent in Spanish and whose wife was born in Mexico, has backed legal status, but not full citizenship, for illegal immigrants, and supports a controversial Common Core education plan.

"Will it be a disqualifier? It depends on how he runs his campaign," said Katon Dawson, a former Republican Party chairman in the key state of South Carolina. "He has the talent to do that. But he'll be running against some major competition."

PREPARATIONS

Bush decided to make a move because he was getting the sense that critical donors and staffers were being snapped up by other potential candidates, the person close to Bush said.

His timeline was also accelerated by a potentially politically damaging story by Bloomberg Businessweek detailing his private equity dealings.

Should he run, Bush's campaign team is unlikely to include many veterans of his father's or brother's administrations, according to a top Republican fundraiser who has spoken with him.

Bush's allies see Paul and New Jersey Governor Christie as his two most aggressive opponents, with Wisconsin Governor Scott Walker as a potentially formidable rival.