At the inaugural GOP presidential debate, a swing-state governor with a record of reforms and a message of economic mobility made his mark. Entering the debate stage to loud applause, the experienced GOP executive touted his brand of compassionate conservatism. He disarmed skeptics of his free-wheeling speaking style, coming prepared with crisp talking points advocating his governing record.

That governor wasn't former Florida Gov. Jeb Bush. It was current Ohio Gov. John Kasich.

"Kasich is killing it. Hopeful. Uplifting. Optimistic. And he has an appeal to those who think the GOP doesn't care," tweeted Ari Fleischer, former spokesman for George W. Bush.

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If there's one immediate consequence of the hyped first Republican presidential debate, it's that millions of American viewers will be learning about many GOP candidates after knowing little about them beforehand. And one of those lesser-known but highly-accomplished candidates is Kasich, the two-term governor of the politically-pivotal battleground state.

Kasich isn't going to win over many of the party's conservative grassroots. But he's not Jon Huntsman, either. Through the course of the debate, he made a compelling case that he's as viable a contender for the establishment mantle as Bush, who seemed unusually tentative and rusty after not being on a debate stage for over a decade.

Throughout the debate, Kasich essentially cribbed Bush's "right to rise" message with his own flourishes. "Lift everybody, unite everybody, and build a stronger United States of America again. It will be, it can be done," Kasich said. He reiterated his opposition to gay marriage, while outlining his personal tolerance for those with differences. "We need to give everybody a chance, treat everybody with respect, and let them share in this great American dream that we have." After outlining the state's record of economic growth, he concluded his closing statement by saying: "People have hope again in Ohio!"

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Kasich sounded like a happy warrior on stage, a far cry from his reputation for irritability. And he stayed mostly on message during his speaking time, an impressive feat for a politician who's known to go off on distracting tangents.

Bush made no major blunders, but he looked out of his element at times. It was clear that his free-wheeling style and aversion to the choreography of politics was preventing him from making a bigger mark. He stumbled (again) over a question about his brother's decision to invade Iraq, clumsily pivoting to Iran at the end. He wasn't as forceful on his key issue—immigration reform—as he could have been, especially with Donald Trump standing next to him on stage. "He seemed a little pale, a little flat," Fox News moderator Chris Wallace said in the network's post-debate coverage.

Bush didn't look like the confident front-runner on stage Thursday night—and he's been stagnant in recent polling despite his name identification. If there's room for an establishment alternative, Kasich is well-positioned to capitalize. The Ohio governor's deliberate line of being the "son of a mailman" offers a stark contrast to Bush's elite upbringing. And if style matters as much as substance to Republicans—something that Donald Trump's surge has demonstrated—Kasich's ability to connect with voters emotionally trumps Bush's ability to do the same.

(RELATED: I Stayed Off Twitter and Watched the Debate Like a Normal Person)

New Hampshire is shaping up to be ground zero for that wide-open battle, one where Kasich has been focusing his efforts and rising in the polls. The Ohio governor's super PAC has already spent about $3 million to raise his profile in the state—and his spending has gotten some results. The RealClearPolitics average of polling in the state finds Kasich surging to fourth place this month, winning over 8 percent of the vote.

The next month will provide a test of whether Kasich can translate that potential into national support. With millions of viewers getting their first exposure to him, he took every advantage of the opportunity. Jeb Bush looked like an awfully tenuous front-runner Thursday night.

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