MIAMI (AP) — Sen. Marco Rubio entered the presidential race Monday by offering the nation a younger generation of leadership that breaks free of ideas “stuck in the 20th century,” a jab at both Democratic favorite Hillary Rodham Clinton and his one-time Republican mentor, former Florida Gov. Jeb Bush.

Standing in front of a banner that proclaimed “A New American Century” and repeating that refrain throughout his kickoff speech, the 43-year-old Cuban-American used his first turn as a Republican presidential candidate to take on two of America’s political dynasties. In doing so, he bet heavily on the electorate’s frustrations with Washington and his ability to change how his party is seen by voters.

“This election is not just about what laws we are going to pass,” Rubio told his evening rally. “It is a generational choice about what kind of country we will be.”

He said it’s also a choice between the haves and have-nots, nodding to his own upbringing by working-class parents.

“I live an exceptional country where the son of a bartender and a maid can have the same dreams and the same future as those who come from power and privilege,” Rubio said.

Earlier in the day, the first-term Republican from Florida spoke to his top donors and told them many families feel the American Dream is slipping away and young Americans face unequal opportunities. He’s banking on the hope that he, alone among many GOP rivals, can make inroads with groups that have long eluded Republicans — young people, minorities and the less affluent.

“I feel uniquely qualified to not just make that argument, but to outline the policies that we need to have in order to achieve it,” he said on the donor call.

In his televised speech, he told supporters, “The time has come for our generation to lead the way toward a new American century.”

Rubio’s remarks came as Clinton was traveling to Iowa on her first trip as a candidate. Her entrance into the race with an online video Sunday is robbing some attention from Rubio’s splash into the race.

But Rubio saw an opportunity to cast the presidential contest as one between a fresh face representing a new generation of leadership and familiar faces harking back decades — namely, the 62-year-old Bush and the 67-year-old Clinton.

“While our people and economy are pushing the boundaries of the 21st century, too many of our leaders and their ideas are stuck in the 20th century,” Rubio said to applause.

The swipe at Bush was implied; with Clinton, he was more direct.

“Just yesterday, a leader from yesterday began a campaign for president by promising to take us back to yesterday,” Rubio said to jeers. “Yesterday is over and we are never going back.”

Supporters began lining up in 87-degree heat three hours before the public kickoff at Freedom Tower, the Miami landmark that was the first stop for tens of thousands of fleeing Cuban exiles during the 1960s and 1970s.

Kelly Steele, 50, and her 18-year-old son wore tie-dyed Rubio T-shirts.

“We have had a lot of Bushes,” Kelly Steele said, comparing Rubio to a youthful John Kennedy.

“Sen. Rubio kind of reminds me of JFK,” she said. “He’s got that energy and desire and momentum and excitement.”

Hours before his rally, the chairwoman of the Democratic National Committee, Rep. Debbie Wasserman Schultz of Florida, criticized Rubio as just another establishment Republican with no new ideas.

“He’s a follower, peddling the same tired Republican playbook,” she told reporters. “Marco Rubio has pandered to the Republican base throughout his whole career.”

To counter views of him as a neophyte, Rubio has outlined specific policy proposals both on foreign and domestic issues. He plans future presentations as his campaign gets underway.

On Tuesday, on his first day as a candidate, he is set to return to Washington to join a Senate hearing on a proposed deal with Iran on its nuclear ambitions.

Rubio faces steep challenges to the nomination, including a well funded one that Bush is expected to offer. The son of one president and brother of another, Jeb Bush was governor while Rubio was speaker of the Florida House. The two formed a close bond, but a presidential campaign was certain to test the strength of their friendship.

Rubio is the third major GOP contender to declare himself a candidate, after Sen. Ted Cruz of Texas and Sen. Rand Paul of Kentucky, in a field that could grow to 20 or more.

Rubio could make history as the nation’s first Hispanic president — as could Cruz.

Philip Elliot (reporting from Washington) and Brendan Farrington, Associated Press