Jeb Bush and Marco Rubio are on course for a collision.
There once was mutual public deference. But that has eroded as the Florida Republicans battling for the presidential nomination have come to see the other as the main threat to lofty ambitions: Bush claims the party establishment's mantle, Rubio wants be the party's fresh national face.
Bush now routinely compares Rubio's background to Barack Obama's before the Democrat became president. Rubio says it's "time to turn the page," a reference that strikes as hard at Bush's long family legacy as it does at Democrat Hillary Rodham Clinton.
The rise of GOP outsiders such as Donald Trump and Ben Carson has increased the stakes for Bush and Rubio as they try to become the mainstream alternative. Whoever wins this internal contest will show whether experience or fresh leadership is the bigger priority for GOP centrists.
From Bush, there's a sense of urgency in his contention that Rubio, in his first Senate term, has not proved his leadership credentials. The ex-governor and his team are frustrated, too, that this shortcoming they attribute to Rubio has not become more of a liability for him.
It's part of the mantra Bush has repeated since the Republicans' second debate in California a month ago, when Rubio won praise for staying above the fray. He has since drawn nearly even with Bush in national polls, although both remain in the high single digits.
"We've got a president that the American people supported based on the fact that he was an eloquent guy," Bush said in Iowa last week. "And he had nothing in his background that would suggest he could lead."
Though describing Obama, it's a slight to Rubio. He delivers a compelling story about his parents' flight from Cuba and his working class background, but he has been in the Senate less than five years and has missed much of its business this year while campaigning for president.
Evidence of the tension between the Florida politicians was on display Thursday whenRubio's campaign, minutes after the Bush organization announced raising $13.4 million in the last quarter, boasted it had more cash on hand. Rubio reported having nearly $11 million in his coffers compared with Bush's $10 million. But about $1 million of Rubio'scash cannot be accessed unless he wins the GOP nomination, a point Bush campaign spokesman Tim Miller pounced on via Twitter.
"Lying about budgets. Guess Marco picked up something in the Senate," Miller tweeted Friday.
Rubio's campaign reported raising $5.7 million from July through September, down from $9 million in the three months prior. Bush's team says that shows he's been losing steam.
Yet Bush advisers are clearly put off by the senator's durability. Hopes have not come to pass that rivals could be chased from the field with Bush's mammoth fundraising effort in the first half of the year — yielding more than $100 million for his campaign and the super PAC supporting him.
They are competing for many of the same voters. Each has won statewide election — Bush twice, Rubio once — in Florida, a hefty prize in the presidential election.
They also have pull among Hispanic voters, whom Republicans want to draw away from Democrats. Both men speak fluent Spanish.
Yet both have been surpassed in the early months of the primary campaign by the billionaire Trump and retired neurosurgeon Carson. Those challengers have ridden dissatisfaction with the government to a lead in national and early state polls with four months before Iowa leads off the 2016 voting.
Rubio is more subtle than Bush as the two men draw distinctions between each other, but his meaning is unmistakable.
In New Hampshire recently, Rubio said the election is "a generational choice" and political leaders in both parties are "out of touch." Rubio is 44, Bush is 62.
"We will not change direction if all we do is keep electing the same kind of people," Rubiosaid in Portsmouth. "This election cannot be one of those elections where we just promote the next person in line, where we just vote for the person the experts tell us we have to vote for."
The remarks are aimed as much at Bush, whose father, George H.W. Bush, was elected president 27 years ago, as at Clinton, whose husband defeated the elder Bush for re-election 23 years ago.
The connections between Rubio and Bush go back to the late 1990s when Bush, then governor, contributed $50 to Rubio's campaign for a West Miami commission seat. WhenRubio became the first Cuban-American to ascend to Florida House speaker, Bush gave him a sword to remind him to stay true to his conservative values.
"I can't think back on a time when I've ever been prouder to be a Republican, Marco," Bush said then. Rubio in his memoir, "An American Son," praised Bush's "creativity and daring."
"Jeb is my friend," Rubio told reporters in Florida when asked about Bush's jabs. "I have tremendous respect for him as a person and for what he did for Florida as governor."
Those jabs are more frequent now, but Rubio is countering from his corner.