By Matt Frei
BBC News, Washington
In a time of flux and flip-flopping, consider the tragic constancy of Senator John McCain.
John McCain's 2008 White House campaign appears to be faltering
While other candidates are tying themselves into squishy rhetorical pretzels about the Iraq war and what they really thought about it in 2002, Mr McCain is the long stick of French bread, stiff with age and greening with mould.
I saw him at the Virginia Military Institute in April, when he tried to re-boot his campaign with a series of speeches about the war in Iraq and the need to stay put, stand firm and send more troops.
It was neither the most rousing speech nor the most electrifying delivery. But it was poignant and plausible. It had a coherent argument delivered with a sense of urgency.
He spoke in front of giant mural of the Civil War battle of New Market and for a moment I could see General McCain in tattered uniform, egging on the Union troops in a decisive junction of a bloody war.
As it happens, Mr McCain read from a giant autocue that hovered like an electronic tablet above the shaven heads of hundreds of cadets. They listened carefully, applauded politely and the ones we spoke to later seemed to agree with him.
As a Vietnam war hero and five-year resident of the Hanoi Hilton, Mr McCain has earned a respect that he doesn't need to fight for. Senator John Kerry, the Democratic candidate in 2004, kept drumming on about his valour on the Mekong.
Mr McCain doesn't even need to mention Vietnam. You can see it in every fibre of his body. You can practically hear the North Vietnamese torturers in the senator's mercurial blue eyes. And as a former recipient of torture, he has consistently condemned its use, however ambiguous, by the administration.
His CV precedes him effortlessly and the senator from Arizona will never be "Swift Boated", unlike Mr Kerry. Instead he may well drown in the churning wake of the administration's sinking Iraq policy.
What has weighed him down even further is his constant and admirable support for immigration reform, the other Bush policy that is almost as unpopular as Iraq and has seen a mass defection of Republicans.
The senator's support for the troop surge in Iraq may drag him down
John McCain is being punished for being consistent and loyal. How ironic that this should be the fate of the plucky outsider who almost defeated George W Bush in the race for the 2000 nomination and whose Straight Talk Express campaign bus nearly rammed Bush's smooth talk wagons off the road.
I asked Mr McCain whether he'll go down in history as the candidate who was twice defeated by George Bush: once for opposing him and once for sticking by his side. He narrowed his eyes, cleared his throat, evinced a fleeting laugh verging on a croak and moved on to the next question.
After the senator's speech, his staffers and handlers high-fived each other. The relief was etched on their pale faces. Recovery was at hand.
That was in the bloom of spring. Now is the sultry heat of summer. Two of those advisers have quit this week.
Mr McCain's fundraising efforts pale beside those of Barack Obama
As the New York Times pointed out with Big Apple sourness, one of the advisers, John Weaver, a long-time friend, even gave up his rent-controlled apartment in Greenwich Village to move down to swampy Washington DC and run the campaign. Losing a campaign is a setback. Losing a rent-controlled apartment in Manhattan for a lost cause is a tragedy.
Add to that the fact that Mr McCain, once considered the undisputed frontrunner in a party that traditionally respects the pecking order, only has $2m (£1m) left in the kitty and the die appears to be cast.
Fundraisers are like rats: they all head in one direction when the waters rise. Ron Paul, the quintessential outsider in the Republican pack also has about $2m. Compare their sums to the $32.5m that Senator Barack Obama has managed to raise in the last quarter or the estimated $200-$350m of his own money that former Governor Mitt Romney can dip into on a rainy day.
Painkillers and panaceas
But the biggest problem that Mr McCain has is not even his lack of money or his support of the president's unappealing policies.
Call it unfair, but his ramrod principles look inflexible these days. His seriousness and poignancy appear grumpy or short-tempered and his ripe old age of 70 makes him look more frail than wise.
Three years ago, when most Americans still believed the Iraq war could be won, Mr McCain's qualities would have swept the board. Had Kerry managed to pick him as his running mate - as was widely rumoured - he might even have won.
But today America is fed up. Independent voters are rooting around for something new and fresh. Republicans are looking for painkillers and panaceas. Almost everyone yearns for escape. And John McCain offers none of the above.
If he bows out of the campaign - and he insists that he won't - I suspect his rivals will actually miss him.
While he beat the drum of sacrifice in Iraq they could keep more quiet on the sidelines and let him do the talking.
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