Story highlights "If I thought he was unstoppable, I'd go back to Ohio tomorrow," John Kasich says of Donald Trump

"Nobody in the country knows who I am. I'm not a celebrity candidate," he added

Washington (CNN) Ohio Gov. John Kasich made the case for his candidacy Tuesday by touting the $4 million in ad money opponents are spending against him.

"The campaigns are spending $4 million of negative ads against me. You think they're worried? They don't spend $4 million ahead of somebody at the bottom," he told CNN's Alisyn Camerota on "New Day."

Donald Trump maintains a wide lead in the Republican primary race in New Hampshire, according to a CNN/WMUR poll conducted by the University of New Hampshire Survey Center and released Sunday.

Overall, 30% of likely Republican primary voters back Trump, and behind him, the field vying for second includes Texas Sen. Ted Cruz at 12%, Florida Sen. Marco Rubio at 11% and Ohio Gov. John Kasich at 9%.

Cruz tallied a victory in Iowa over rivals Trump and Rubio on Monday night.

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