Greenville, South Carolina(CNN) Coming soon: Marco Rubio 2.0.
The Republican candidate, who lost momentum this week after coming in fifth in New Hampshire, plans to take a more aggressive tone with some of his rivals -- especially if they attack him on the debate stage -- and is expected to showcase more of his affable personality in order to rebut criticism that he is a scripted candidate.
As one aide put it, "Let Marco be Marco."
In a shift, Rubio had a 44-minute free-flowing conversation with reporters on his campaign plane en route to Greenville. Relaxed, talkative and reflective, he spoke about his debate gaffe, criticisms of him being too scripted and his path to the nomination. His team hopes to show more of this side of him, including with more focus on his hardscrabble personal story and being the son of working-class Cuban immigrants.
And above all else, he vowed to bounce back.
"You want to have a president who went through adversity in a campaign," Rubio said.
READ: New Hampshire primaries: 5 takeaways
Despite his rivals' attacks that he comes across as scripted, Rubio argues it's better to be consistent than not. Voters don't pay as close attention to things as campaign reporters, he said.
"Just because it's the 80th time you heard it may be the first time someone else heard it," Rubio said of his speeches.
Rubio doesn't believe he needs to win any of the first four primaries. He just needs to stay in the top tier of candidates into March and then come in first in the winner-take-all states from March 15 on, adding that he has no "firewall" state unlike some of his foes.
"I don't think anyone is going to wrap this up in South Carolina or Nevada," he said. "Once you get to the winner-take-all states, then it's about winning."
READ: Presidential candidates: South Carolina, here we come
When it comes to his rivals, Rubio said front-runner Donald Trump lacks national security experience and must explain his views more thoroughly. Voters will want to know whether their nominee knows the difference between ISIS and al Qaeda and that Russian President Vladimir Putin is trying to assert influence in the Middle East, among other things, he said.
"Once the race narrows, the pressure is going to be on him (to detail his views). I don't think you can keep saying 'trust me,'" Rubio said.
Rubio added: "I don't think he's shown any in depth understanding of the issues." While he said Trump has said some "entertaining stuff, some of it is not so entertaining."
As he heads into the South Carolina primary, Rubio is battling hard to become the alternative to Donald Trump. And his former mentor, Jeb Bush, is now his biggest hurdle standing in his way.
Rubio would not acknowledge that losing to Bush here would be detrimental to his campaign. But Rubio said the former Florida governor spent a historic amount of money in New Hampshire, but only finished 1,500 votes ahead and won the same number of delegates. He criticized Bush, saying the "party needs to turn the page" and describing himself as more attune to the needs of the 21st century.
"I have more experience in foreign policy and national security than he does," Rubio said. "I just do."
Clearly unafraid of John Kasich, Rubio called the Ohio governor "an impressive guy" whom he likes. Though he added that Kasich, a former congressman, hasn't dealt with foreign policy in a "long time."
And Rubio said he wasn't upset at New Jersey Gov. Chris Christie for going after him at Saturday's debate, when the Florida freshman repeated the same line three times -- despite being directly criticized for sticking to the script. But he said he learned a valuable lesson: To fight back "frontally" when he's being criticized.
"I don't need to start these fights, but if someone starts one in the future, we are going to point out the differences in our records in a sharper way," Rubio said.
Asked why he didn't attack Christie during the debate, Rubio called it a "strategic decision that turned out to be wrong" and that he didn't want to use "valuable" air time to attack the New Jersey governor.
"Obviously, we can't let that happen again," Rubio said.
Aboard his flight, Rubio spoke with reporters until they ran out of questions. It was unusual for the candidate, who has typically held media availabilities that last just minutes, with an aide hand-selecting reporters to ask one question at a time. This time, it was casual -- and he wasn't afraid to offer some self-deprecating humor.
When asked if his debate missteps were like then-Texas Gov. Rick Perry's infamous "oops" moment in 2012, Rubio said: "There's a big difference. He couldn't remember what he wanted to say. I remembered it too well."