Kasich: I have a plan, they have fantasies

Gov. John Kasich took aim at his fellow Republicans Wednesday night, calling their tax plans a "fantasy."

"These plans would put us trillions and trillions of dollars in debt," Kasich said. "I'm the only one on this stage that has a plan that would create jobs, cut taxes, and balance the budget, and can get it done, because I'm realistic."

The comments came after opponent and one of the leading contenders, Ben Carson, said he would support a flat tax plan at rates close to 15 percent, and would cut from government programs to make up for lost tax revenues. That move would require cuts to 40 percent of the government, according to CNBC analysis.

"We have 645 government agencies and sub agencies," Carson said. "Anybody who tells me we need every penny in everyone of those is in a fantasy world."

Kasich responded that folks "need to wake up." But businessman Donald Trump fired back at Kasich's experience balancing budgets, saying he "got lucky" with fracking.

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Tax reform is one of the few issues where almost every GOP candidate has issued a robust platform on their campaign website. Many of the 2016 candidates believe that Americans pay too much in taxes, and the code needs to be simplified.

But is it a question of pulling back existing rates, or moving to another system all together?

Marco Rubio, Jeb Bush, Chris Christie, Donald Trump and others have previously proposed cutting current tax rates to 8 to 35 percent, depending on the bracket, with various reforms to marriage and child credits and capital gains, corporate and estate taxes. Candidates like Ted Cruz, Ben Carson, and Rand Paul said they support replacing the current tax system with a simpler form of flat tax.

Mike Huckabee called these plans "putting lipstick on a pig," and told CNBC he would promote replacing income tax (and the IRS) with higher sales tax

Candidates discussed the issue Wednesday night as part of a two-part televised debate, where Republican hopefuls vied to debate their way to the party's nomination for president in 2016.

A poll by The New York Times and CBS this week put retired neurosurgeon Ben Carson at the front of the pack of candidates, with 26 percent of Republican primary voters, trailed by Donald Trump at 22 percent, Marco Rubio with 8 percent, and Carly Fiorina and Jeb Bush with 7 percent of the vote, each.

That's compared to an Oct. 20 NBC News/Wall Street Journal poll, which showed real estate mogul Trump leading with 25 percent of the vote, followed by Carson in second place with 22 percent. Rubio ranked third with 13 percent, ahead of Cruz with 9 percent and Bush with 8 percent.

— CNBC's John Harwood and Anita Balakrishnan contributed to this report.