(Adds earlier McCain comments, para 11)

By John Whitesides, Political Correspondent

CLEVELAND, May 1 (Reuters) - Republican presidential candidate John McCain said on Thursday he would be reluctant to ever declare "mission accomplished" in Iraq, but suggested rosy early predictions of success there by President George W. Bush and other officials fueled public frustration with the war.

On the fifth anniversary of Bush's victory speech under a banner declaring "Mission Accomplished" in Iraq, McCain said the administration mishandled the war's early stages and raised public hopes by calling the remaining insurgents in Iraq "dead-enders" in their "last throes."

"I thought it was wrong at the time," McCain told reporters in Cleveland, where he continued a week-long tour to discuss his health care plans.

"I thought phrases like 'a few dead-enders,' 'last throes,' all of those comments contributed over time to the frustration and sorrow of Americans," he said. "Those were, unlike the banner, direct statements that were contradicted by facts on the ground."

McCain, who has clinched the Republican nomination in November's presidential election, is a staunch advocate of the war and a supporter of the increase in U.S. troops in Iraq under Gen. David Petraeus.

But he said he would not make a similar "mission accomplished" declaration in Iraq in future years no matter how much progress is made.

"I'd hate to use that kind of language," the Arizona senator said, adding success in Iraq would be "two steps forward and one step back."

"I don't know if you could ever say, quote 'mission accomplished,' as much as you could say 'Americans are out of harm's way.' And that's the key to America's concern -- casualties," he said.

McCain has argued Americans will be willing to accept a lengthy but reduced U.S. troop presence in Iraq if casualties end, making the deployment more like the extended U.S. presence in South Korea.

WITHDRAWAL COULD MEAN CHAOS

He has criticized calls by his Democratic presidential rivals, Sens. Barack Obama of Illinois and Hillary Clinton of New York, for a quick withdrawal of U.S. troops from Iraq. He says that will lead to chaos in the region and eventually require an American return.

But McCain's critics said he made many of the same optimistic predictions at the onset of the war, including a June 2003 comment that "the major conflict is over."

"Five years after George Bush declared 'mission accomplished' and John McCain told the American people that 'the end is very much in sight' in Iraq, we have lost thousands of lives, spent half a trillion dollars, and we're no safer," Obama said in a statement.

The liberal grass roots group MoveOn.org launched a $1 million month-long ad campaign against McCain on Thursday highlighting the banner's fifth anniversary and McCain's comment from January that U.S. troops could be in Iraq 100 years.

McCain's full comments at the time made clear he was referring to a peacetime presence without casualties, and Republicans attacked the ad. McCain said the ad was "falsifying" his position.

"I think the record is pretty clear that I came back early on after the initial military success and argued vehemently against the strategy that was failing there and advocated for the strategy that in my view is succeeding," he said.

"So I'll put my trust in the voters of this country that I know how to lead and that I have the experience and the knowledge and the background to make those judgments," the former prisoner of war in Vietnam and Navy fighter pilot said. (Editing by David Wiessler) (To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at http:/blogs.reuters.com/trail08/)

AlertNet news is provided by