TALLINN, Estonia — For six months, former Florida governor Jeb Bush has been running for president while demurring that he is not an official candidate. With the fan-dance phase of the campaign about to end, he offered a peek Friday at the "hopeful, optimistic" themes he plans to sound when he makes his formal announcement Monday.

Bush is spending the final days of his pseudo-candidacy on a swing through Germany, Poland and Estonia, part of an effort to burnish his credentials as a potential commander-in-chief.

“I’ve been thinking about what I’m going to say, for sure, and prior to this trip," he told reporters. "I hope that the message will be a hopeful, optimistic one. It won't dwell too much on the past. I will talk about why it is important to change directions. I will talk a little bit about, hopefully, the leadership skills that are necessary to solve problems."

He also indicated, however, that he will offer his two terms of governor of Florida as evidence of how he would run the country.

"I had the opportunity as governor of a state where a lot of things happened. Some people liked them. Some people didn’t. But there’s no question, you ask friend and foe alike, that Florida was changed by my leadership, and I think it changed for the better," Bush said. "And so I’ll talk about that. And there will be some lines of good humor as well, I hope."

When Bush first announced his interest last year, surprising many Republicans, he had seem poised to move to the head of the field as the favorite of the GOP establishment. But despite the advantages of his pedigree, his family's political network and fundraising capabilities, he has yet to break out in the early polls. One obstacle is the perception that he is too moderate for a party that has swung to the right.

Two days before Bush officially joins the crowded field of candidates running to be the 2016 standard-bearer, Democratic front-runner Hillary Clinton will hold a major rally in New York City. Asked about her candidacy, Bush demurred for now, saying that domestic political battles should not be waged by candidates when they are overseas.

"Mrs. Clinton was secretary of state for four years under President Obama. She has a record. It is a record she will have to defend, and I believe that this is not an appropriate place to be talking about American politics," he said. "There will be ample chances to show the differences between myself and Hillary."

One challenge for Bush on that score will be navigating around his own last name, and the memories it invokes of the foreign policies of the last two Republican presidents, who happened to be his brother and father.

As he traveled through Europe this week, Bush often invoked the deft, widely admired manner in which the 41st president, George H.W. Bush, operated as the Cold War ended. He has not mentioned the more unpopular, unilateralist approach of his brother, George W. Bush, who was the 43rd president.

His itinerary reinforced those themes. On Friday, he was briefed by officials at the NATO Cooperative Cyber Defence Centre of Excellence here, which functions as a sort of think tank for the North Atlantic Treaty Organization and is run by some of the member nations of that Western alliance. He also met with Estonian Foreign Minister Keit Pentus- Rosimannus, and was scheduled to dine with Estonian President Toomas Ilves at the presidential palace.

"If you think about it in terms of history, my dad’s managing of the cooperation with great leaders of his time, managing the fall of the Soviet Union, it has been talked about at every stop that we’ve made," Bush said.

He said that when he was in Poland on Wednesday and Thursday, he was often reminded of the 1987 speech that his father gave in Krakow, which the elder Bush insisted be carried uncensored on national television there.

"It was a spark," Jeb Bush said. "It was something that was so breathtaking for Poles who could never believe anything that they saw on television. Think about how much change has taken place in these years. It’s a good reminder that we're a lot freer now than we were, and we need to protect that freedom. And that’s why the United States needs to be engaged."

With Bush in Europe, aides at his campaign headquarters in Miami have spent the past few days putting the finishing touches on what's promised to be a dramatic and social media-driven launch.

Bush will launch his bid Monday afternoon at Miami Dade College with an announcement speech expected to last about 15 minutes. His remarks will touch on three general themes, according to aides familiar with the plans.

First, Bush will embrace the atmospherics of the campus, part of a public university system with more than 10 locations across South Florida that boasts the nation's largest Hispanic student body. Bush has spoken at the college several times, and his brother, George W. Bush, delivered a commencement address there in 2007. Aides said Bush considers the venue an ideal place to launch a campaign expected to make aggressive overtures to the country's expanding Latino voting population and other groups less prone to support GOP candidates.

Bush also plans to cast himself as a proven "fix it" agent, who revamped Florida's economy and government over eight years while enacting a conservative governing agenda. The defense of his record will serve as a direct contrast with the four presidential candidates serving in Congress: Sens. Ted Cruz (Tex.), Lindsey O. Graham (S.C.), Rand Paul (Ky.) and Marco Rubio (Fla.).

Over the course of his early travels, Bush has often used the phrase "Right to Rise" — a moniker that is also the name of his leadership PAC and a super PAC poised to support his candidacy. Bush and his campaign are expected to provide a fuller definition of the phrase in the coming days, starting with testimonials from people who say they were helped by his work as governor or as an education reform advocate in the years since.

Once Bush launches his campaign, he's planning a whirlwind, three-day tour of New Hampshire, Iowa and South Carolina, with several public events and private meetings scheduled. Aides said that Bush is likely to continue the format of the public appearances he's held during his exploratory phase, which generally include a brief opening speech followed by roughly 45 minutes of questions from attendees.

On Friday, he also got an early boost of support from several senior Florida Republicans —  a blow to Rubio, another popular statewide elected official.

Among those pledging to back Bush are Pamela Bondi, the state attorney general; Jeff Atwater, the state's chief financial officer; and Adam Putnam, the state agriculture commissioner. Eleven of Florida's 17 Republican congressmen are also backing him, including Miami's three Cuban American lawmakers: Reps. Ileana Ros-Lehtinen, Mario Diaz-Balart and Carlos Curbelo. Several others, including Reps. Dennis Ross and Gus Bilirakis, have long ties to Bush, dating back to before he won the governor's office in 1998.

O'Keefe reported from Washington.