By CNN's Wolf Blitzer

(CNN) – The Republican presidential debate in Iowa was lively. It showed that the eight candidates on the stage can in fact throw punches not only at President Obama, but also at each other, and even at the debate moderators.

By and large, they ignored President Reagan’s old 11th Commandment: “Thou shall not speak ill of any fellow Republican.”

The exchanges between Tim Pawlenty and Michele Bachmann were intense.

Newt Gingrich’s blasting of the Fox News questioners was surprising given that he used to work with them.

Ron Paul showed that he’s not afraid to move away from the conventional Republican positions on Iran, Iraq and Afghanistan.

Rick Santorum minced no words lashing out against Paul, and Paul hit him right back.

Mitt Romney, arguably the front-runner, largely stayed above the fray – which, for a front-runner, is smart. But he has to start worrying big time about Texas Gov. Rick Perry, who could pose a real challenge to the former Massachusetts governor.

All eight candidates raised their hands when asked if they would reject even a lopsided 10-to-1 proposal to reduce the nation’s deficit – meaning cutting $10 of government spending for every $1 of increased taxes. They obviously take their “No New Taxes” pledge to Grover Norquist’s Americans for Tax Reform seriously. Even Jon Huntsman, the former Utah governor, raised his hand even though he didn’t sign the pledge.

I’ll have my chance to question the GOP candidates when I moderate the presidential debate in Tampa on September 12.

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