Washington (CNN) Sen. Lindsey Graham said Monday that the Iraq War was not a mistake, even though he was less certain whether he agreed with the ground invasion authorized by President George W. Bush in 2003.

Graham was the latest presidential hopeful to tangle with the thorny hypothetical posed to many in the burgeoning Republican field over the past week: Would they have ordered the invasion of Iraq knowing that the nation did not have weapons of mass destruction?

"If I knew then what I know now, a land invasion may not have been the right answer," Graham told CNN's Wolf Blitzer on "The Situation Room," detailing the record of abuse and rogue behavior by Saddam Hussein. "He had a lot to do with destabilizing the region."

Graham later said he would have "kept the pressure to get rid of Saddam," though he did not detail what that would mean.

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