WASHINGTON Republican John McCain's top two aides left his struggling U.S. presidential campaign on Tuesday, dealing a sharp blow to the Arizona senator and casting doubt on the future of his 2008 bid.
McCain said he would continue his White House run despite the departures of manager Terry Nelson and longtime chief strategist John Weaver, which were announced as McCain took the Senate floor to defend President George W. Bush's strategy in Iraq.
Once a front-runner in the Republican field, McCain has fallen behind as his staunch backing for Bush on the unpopular Iraq war and on an overhaul of immigration laws cost him support among both moderates and conservatives.
"We've had ups and downs in other campaigns and we'll have ups and downs with this campaign. I'm very happy with where we are," McCain told a crush of reporters at the Capitol, promising to "out-campaign" his rivals.
Nelson was Bush's political director during his 2004 re-election campaign and Weaver was McCain's top strategist during his unsuccessful 2000 race for the White House. In statements released by the campaign, neither man offered a reason for leaving.
"I believe John McCain is the most experienced and prepared candidate to represent the Republican Party and defeat the Democratic nominee next year," Nelson said.
Rick Davis, McCain's campaign manager in 2000 and chief executive officer of this campaign, will take over managing McCain's White House run.
The shake-up follows last week's campaign reorganization and cutbacks in staff, the result of a weak fund-raising quarter that left McCain with just $2 million in the bank.
McCain has been lagging behind former New York Mayor Rudy Giuliani in polls, and trails Giuliani and former Massachusetts Gov. Mitt Romney in raising money for the November 2008 election.
McCain's disappointing take of $11.2 million in the last three months, and his $2 million in the bank, prompted a flood of criticism and questions last week about spending and strategy within the campaign.
A Republican strategist said it would be difficult for McCain's campaign to pull out of its death spiral.
"They can decide to crank up the bus and try to recapture the magic from 2000, but once it's gone it is hard to get back," said the longtime Republican consultant, who asked not to be named. "The fund-raising community just closes their checkbooks."
While a sign of trouble, high-level campaign shake-ups can sometimes produce results. Democrat John Kerry, lagging badly in the polls, fired his campaign manager in late 2003 and wound up winning the nomination months later.
Republican Ronald Reagan dumped his campaign manager on the afternoon of the New Hampshire primary on his way to winning the White House in 1980.
Tuesday's announcement came as McCain, who visited Iraq last week, reiterated his support for Bush's new war strategy and the Senate reopened debate on the issue.
While Democrats are pressing for a plan to withdraw troops and several Republicans have defected from Bush over the war, McCain said it would be a mistake to abandon Bush's strategy now.
"I believe that our military in cooperation with Iraqi security forces is making progress in a number of areas. In other areas they are not," McCain said. "This strategy is the correct one."
(Additional reporting by Susan Cornwell)