Democrats pounced on McCain's comment about U.S. concern that Iran, a Shiite country, has been "taking al-Qaida into Iran, training them and sending them back" to Iraq, The New York Times reported Wednesday. The United States believes that Iran has been training and financing Shiite extremists in Iraq -- but not al-Qaida, a Sunni insurgent group.

McCain made several references to Iran training al-Qaida operatives until he was corrected by Sen. Joe Lieberman, I-Conn., traveling with McCain as part of the delegation.

"I'm sorry, the Iranians are training extremists, not al-Qaida," said McCain who has based his campaign in large part on the claim that he is the best prepared to deal with Iraq, the Times said.

"(He) showed he either doesn't understand the challenges facing Iraq and the region or is willing to ignore the facts on the ground," Democratic National Committee spokeswoman Karen Finney said in a statement.

Brian Rogers, a McCain campaign spokesman, said when McCain misspoke in a news conference Tuesday in Amman, Jordan, he "immediately corrected himself."