With a week to go until the highly anticipated first GOP debate, Charles Krauthammer laid out one of the big strategic questions facing the candidates.

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Krauthammer said each of the ten candidates on the stage will have to decide whether to go after Donald Trump. 

"This is a real dilemma in a big field. If you're the one who takes him on, you could be the one who ends up damaged," said Krauthammer. 

He pointed to the 2004 Democratic primary in Iowa when frontrunners Howard Dean and Dick Gephardt ran ads "savaging each other," allowing John Kerry and John Edwards to "sneak in" and finish first and second respectively. 

"That's the problem if you take on Trump. You might succeed in bringing him down a notch or two, but you may not be the one who benefits. So is there interest that you would have as a candidate in going after him? I don't know what the answer is," said Krauthammer.

O'Reilly said that Ted Cruz might be the one to take on Trump, reasoning that the Texas senator is losing supporters to Trump more than any other Republican candidate. 

Krauthammer disagreed, predicting that Cruz will continue a strategy of "riding in Trump's wake."

Watch the discussion below.

Don't miss the Fox News-Facebook Republican presidential debate, Thursday August 6, live from Cleveland, Ohio at 9p ET, moderated by Megyn Kelly, Bret Baier and Chris Wallace. 

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