Jeb Bush is “a Big Government Republican.” Mitt Romney “had his chance.” And Marco Rubio’s recent jabs on foreign policy are “silly” and “childish.”

Kentucky Sen. Rand Paul is back in insurgent mode, lobbing bombs at his potential Republican presidential rivals and looking to take back a political spotlight that Bush and Romney have been hogging lately. Paul is also heading to New Hampshire and Nevada this week, hoping to strike a fire with voters who want a new voice to carry the GOP’s message to the White House.


“You need a candidate who reaches out to new constituencies and is able to bring new people into the party,” Paul said. “Because if we do the same old, same old candidates, we are going to get the same old result.”

While other Republican House and Senate members attend this week’s rare GOP joint congressional summit in Pennsylvania, Paul will be in New Hampshire to meet with mothers and activists railing against Common Core, the education program reviled by the tea party right. An added advantage: The issue gives him a chance to further needle Bush, a prominent Common Core supporter who would probably be a front-runner for the presidential nomination.

( Also on POLITICO: Rand Paul taps Chip Englander as likely 2016 campaign manager)

In an interview Tuesday, the Kentucky Republican did just that.

“He’s been a proponent of Common Core, a proponent probably of a much bigger government — a Big Government Republican who believes more things should be occurring in Washington rather than decentralization,” Paul said of the former Florida governor. He added that his rival’s brother and father, former Presidents George W. Bush and George H.W. Bush, also backed education policies aimed at “more Washington control.”

Jeb Bush spokeswoman Kristy Campbell responded: “Gov. Bush would put his successful conservative governing record up against anyone’s.”

Paul’s assessment of Romney is only slightly less critical.

“I think you are already hearing rumblings that he had his shot,” Paul said of the GOP’s 2012 presidential standard-bearer. “I think he could have been a good leader of the country. But I think many people are going to say, ‘He’s had his chance.’”

( Also on POLITICO: In speech about New Jersey, Chris Christie talks about the country)

For much of the past year, Paul had a major target on his back as his profile rose in the party and the media dubbed him a potential front-runner in the crowded field of likely presidential candidates. His libertarian-minded foreign policy views became a frequent source of criticism from the party’s defense hawks — especially in light of the U.S. war against Islamic State of Iraq and the Levant militants — as did his lack of executive experience.

But as Jeb Bush has taken serious steps toward a presidential bid, and Romney is now floating a third run at the GOP nomination, Paul appears eager to return to his role as a conservative firebrand, unafraid to take shots at his foes while attempting to consolidate support from crucial Republican factions in the four early presidential primary states. In multiple interviews with POLITICO, Paul also sharply pushed back at Rubio’s criticism of his views on Cuba and even ridiculed the Democratic secretary of state in Kentucky, Alison Lundergan Grimes, who has said he cannot appear on the state’s ballots for both president and the Senate in 2016.

Voters, he said, would look past his lack of executive experience and less than one full term in the Senate and instead back a candidate with a “vision” for the direction of the country. But he also believes voters won’t back a candidate who fails to respond aggressively to attacks.

One example of his forceful response to criticism: After Paul expressed support for President Barack Obama’s decision to normalize relations with Cuba, Rubio responded to a question on the matter by dubbing the Kentucky Republican the “chief cheerleader of Obama’s foreign policy.” But Paul fired back at the Florida Republican and anti-Castro hard-liner in an interview last week.

“That’s sort of silly,” Paul said. “We could ask the same, ‘Is he the biggest cheerleader of Obama’s immigration policy?’ That’s childish.”

( Also on POLITICO: Ted Cruz on Mitt Romney: No need for ‘mushy middle’)

Rubio spokesman Alex Conant declined to comment Tuesday.

A Paul presidential run appears increasingly likely, and his advisers expect an announcement in the March or April time frame. He is building a political apparatus in the key primary states and has settled on a campaign manager, Chip Englander, who ran Republican Bruce Rauner’s successful 2014 gubernatorial bid in Illinois.

Wednesday’s trip to New Hampshire will be his third since the beginning of last year. He will meet with roughly 20 elected officials in Manchester, the start of an effort to win backing from influential state legislators who have pockets of support throughout the state. He’ll then stump alongside pro-gun enthusiasts in Litchfield, followed by swings through Manchester and Concord for meetings with anti-Common Core activists and with business leaders, respectively.

Later in the week, he will head to southern and northern Nevada, traveling for a Friday and Saturday swing to Las Vegas and Reno. Nevada is a state with another pivotal early primary.

With their libertarian streaks, New Hampshire and Nevada both present attractive opportunities for Paul, who may have a much more challenging time competing in Iowa, a state dominated by religious conservatives, as well as the first-in-the-South primary state of South Carolina. In 2012, Paul’s father, former Texas Rep. Ron Paul, took second place in New Hampshire, securing 22 percent of the vote compared with Romney’s 39 percent. The elder Paul came in third place in Nevada, winning 19 percent of the vote.

While Paul will certainly rely on the same passionate voters who fueled his father’s rise, the 52-year-old former ophthalmologist has taken steps to broaden his appeal beyond that segment of the GOP base. How he straddles the line between purity politics and political pragmatism without appearing to pander to voters will be a continuing challenge as he navigates the land mines of a presidential run.

Indeed, in the interview, Paul flatly said, “No,” when asked if his father would join him on the campaign trail should he run.

“It’s just I need to represent the ideas and present ideas, because if I were to run, obviously it’s me running,” he added.

But after comparing his own foreign policy views to those of Ronald Reagan and noting he “grew up as a Reagan Republican,” Paul punted when asked if he would consider himself now to be more of a Reagan Republican or Ron Paul Republican.

I think the thing is I have to express my own ideas of who I am, and people can judge where they come from."

“I think the thing is I have to express my own ideas of who I am, and people can judge where they come from,” Paul said.

For some Republicans, Paul’s views appear straight from the isolationist wing of the party, something they argue GOP voters will greet skeptically.

“I like Rand a lot, but I’ve never been with him on foreign policy,” said Sen. Lindsey Graham, a South Carolina Republican and leading defense hawk. “I think his worldview is out of sync with the times in which we live.”

Asked about the criticism, Paul argued that polls in early states like Iowa show a large number of primary voters would back his contention that the Iraq War was a “mistake” and support a less aggressive U.S. role in the world. “I don’t consider that to be an outlier position,” he said, adding that he would have voted against authorizing war in Iraq in 2002 and that the U.S. should resist attempts to oust secular dictators because of the likelihood it would spawn “chaos.”

Yet he chafes at the characterization that he’s an “isolationist,” saying: “I’m for less intervention, not no intervention. And for being wise when we intervene and for intervening when we actually must intervene.”

But as more conflicts emerge overseas, his opponents will have opportunities to bring some of his more contentious views to light — as Rubio did when asked about Paul’s stance on Cuba.

Rubio, who is also eyeing a White House run, has said he would choose either a Senate or presidential bid in 2016 — but it would be too difficult to do both. Paul, on the other hand, wants to run for both Senate and president in 2016, but he has to perform some procedural jujitsu to overcome a prohibition in Kentucky law against candidates appearing twice on the ballot. If he were to drop out of the presidential race early, the issue would be moot.

But if he were to stay in, Paul would have to rely on untested maneuvers to find a way around the issue in the primary.

The “most likely option,” Paul said, would be for the state GOP to change the presidential primary in the state to a caucus, which presumably would not have paper ballots, sidestepping the problem of appearing on the primary ballot twice. Whether such a move would sustain a legal challenge — and how Paul would handle the Senate race in the general election if he were to win the GOP presidential nomination — remain major questions going forward.

Grimes, the Kentucky secretary of state who lost a bid to unseat Senate Majority Leader Mitch McConnell last fall, said in an email that she “has the same advice for Rand Paul that Sen. McConnell did — he has a choice to make.”

“Kentucky law has prohibited a candidate’s name from appearing on the same ballot for more than one office for more than 50 years,” Grimes said. “I will continue to administer Kentucky’s election laws and ensure all eligible Kentuckians have their voices heard.”

Asked about Grimes’ position, Paul bashed the Democrat, bringing up her decision during the campaign not to reveal whether she had voted for Obama for president.

“She’s confused about a lot of things. She doesn’t even know who she voted for for president — my goodness,” Paul said. “I think she still doesn’t quite understand. She probably needs to read some of the law and learn a little bit more about election law.”

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