Manchester, New Hampshire (CNN) John Kasich locked up an influential endorsement Tuesday night in New Hampshire on the heels of a new poll showing a jump in support for the Ohio Governor in the first-in-the-nation primary state.

Republican operative Tom Rath will serve as senior national adviser and co-chair of Kasich's New Hampshire campaign - Rath is a former New Hampshire GOP Committeeman and state Attorney General. He backed Mitt Romney in 2008 and 2012, and served as national advisor to the presidential campaign of President George W. Bush.

"Our country needs Governor Kasich," Rath said in a statement. "He has a proven track record of balancing the federal budget, reforming our military and turning around one of our nation's largest states. Beyond his accomplishments, Governor Kasich governs in a way that includes everyone. He is sending our country the message that everyone deserves a chance, everyone deserves a voice, and he will help give it to them. That's a powerful message in New Hampshire and the right one for our nation."

Rath joins New Hampshire campaign chair and former New Hampshire Senator John Sununu - who Kasich credited back in June with convincing him to seriously consider a 2016 presidential bid even though few Americans outside Ohio knew who he was.

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