As he embarked on his final two years in office, President Bush this week ensured that the war in Iraq will be the biggest hole in the road to the White House for those who would succeed him.

Democrat and Republican White House hopefuls would have preferred that the issue played no part in the 2008 presidential elections. Mr Bush has, however, rejected a range of exit strategies offered to him by the military and political establishment.

Instead, he has dispatched more troops in a final bid to salvage something resembling victory — and a legacy — from the wreckage of Iraq. For the Republicans, the equation appears simple: the war in Iraq is now supported by scarcely a third of American voters and was the most important factor in the party’s defeat in November’s Congressional elections.

This is why at least half a dozen Republican senators, particularly those mindful of their re-election prospects, have joined the clamour on Capitol Hill to denounce the President’s new strategy.

The picture is more complicated for those seeking the Republican presidential nomination because the party’s activist base — which will select the candidate — remains generally loyal to Mr Bush.

This may be one reason why Senator John McCain, has long argued for an increase in troop levels, based on his experience of Vietnam where, he believes, the war was lost by a lack of political support and funding in Washington.

That view appeared to be a good political strategy. It put him at odds with the unpopular “stay the course” status quo, allowing him to say that America might have won the war, if only the President had followed his advice.

His problem is that Mr Bush appears to have done that this week, giving Mr McCain a sense of authorship over a strategy which few outside observers believe will succeed.

Even the White House is privately talking of a “plan B” of a swift pull-out if the Iraqi Government fails to fulfil its promises.

His chief rivals for the nomination had tried to straddle the fence but Mr Bush’s speech smoked most of them out.

Rudy Giuliani and Mitt Romney this week issued statements supporting the President, with varying degrees of enthusiasm.

Another likely candidate, Senator Sam Brownback, said that he opposed the troop increase proposal.

The Democrats’ victory in November has given them an opportunity to influence policy in Iraq. Those preparing a presidential bid are united in opposition to the Bush plan.

John Edwards has made a strong pitch to the party’s liberal base by supporting a plan for Congress to deny funding for a troop increase. Hillary Clinton, whose support for the war in 2002 — and her cautious criticism of it since — did much to tarnish her lustre among the liberal Democratic selectorate, has remained silent on this scheme.

So, too, has Senator Barack Obama, the current Democratic “it-boy”. Although he rarely misses an opportunity to describe himself as “somebody who thought that going in (to Iraq) was a bad idea in the first place,” he has endorsed only a symbolic vote of protest.

They sense a Republican trap in which, if they block the troop increase, they will be blamed for the mess in Iraq.

Right-wing pundits such as Ann Coulter are setting the Democrats up to take the blame for “betraying the Iraqis who supported us and rewarding our enemies exactly as they did to the South Vietnamese.”

What they say

Republicans

John McCain

Vietnam vet staking his credibility on a sustained increase in troop levels. Is consistent, but knows the policy is unpopular. Says he would “rather lose a campaign than lose a war”

Mitt Romney

Ducked questions about Iraq for months but came off fence this week, backing Bush after (apparently) consulting “generals and ground forces”

Rudy Guiliani

Strong national security credentials as New York mayor on 9/11, but lacks foreign policy experience. Came out in favour of the plan, saying Baghdad’s plight reminds him of the crime levels in New York

Democrats

Hillary Clinton

Criticised for being slow to recant 2002 vote for the war. “I cannot support the escalation of the war,” she said this week, but was silent on whether Congress should block funding

Barack Obama

Opposed war from the outset and says Bush plan is a “very bad mistake”. But wary of denying funds for the surge, saying he does not want to hurt troops in Iraq

John Edwards

Has volubly renounced support for the war. Backs blocking funds for a troop increase which he has branded the “McCain strategy”

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