President Bush has been back on the trail this week. For the highest-profile politician in the world and a man who evidently feels most at home on the hustings, he has been oddly absent in the battle for control of the US Congress that ends with midterm elections next Tuesday.

But on Monday night in Sugar Land, Texas, it was a little like old times. The daily dose of bad news from Iraq, opinion polls that show his approval ratings slumped near record lows, the ubiquitous presentiment of imminent defeat hanging over the Republican Party, were all momentarily banished. Among thousands of still-loyal supporters in his home state, Mr Bush was in fighting form.

“You know what’s interesting in Washington? Some of the folks over there are already picking out their new offices,” he said, mocking the growing optimism among Democrats that they are about to win control of Congress for the first time in more than a decade.

“You might remember,” he continued. “In 2004, some of them were measuring the drapes in the West Wing . . . Their problem was, the movers weren’t needed. And the same thing is going to happen this year.” The message was a familiar one from Bush campaigns past. Don’t underestimate the political skills of this consistent overachiever.

Democrats certainly have made that mistake time and again. In 1994 when he first ran for Governor of Texas, few gave him much of a chance against the popular incumbent, Ann Richards. In 2000, facing Al Gore, he seemed up against impossible odds as he challenged an incumbent vice-president at a time of unparalleled peace and prosperity. In 2002 he reversed all historical precedents and helped his party to gain seats in midterm elections for the first time in 50 years.

And in 2004, as the President noted this week, much of the world went to bed on election night thinking that they would wake up to the clamorous victory celebrations of president-elect John Kerry, but discovered (mostly to their dismay) that Mr Bush had beaten the odds once again.

Mr Bush is not on the ballot in Tuesday’s elections. He has another two years in office, whatever happens next week. But political substance is sometimes rather different from constitutional formality and this is, for all practical purposes, Mr Bush’s last campaign. Not just because he is the incumbent President — nor because what happens could change the way he is forced to govern for his last two years — but because this vote, even more than that of 2004, is in large measure a vote of public confidence in George Bush.

And this time, unlike all those other occasions, the prospect of defeat looks more likely than ever to be matched by its reality.

Many factors will determine the way voters choose next week — national and local considerations are a complex matrix of electoral decision-making. But the Bush presidency is very much on the ballot.

If the Democrats seize control of the House, as looks very likely, and the Senate, which looks possible, they will not simply have power to constrain and hound the President. Their victory will mark a dramatic setback for Mr Bush’s foreign and domestic agenda and will spark a bout of soul-searching within the Republican Party about the wisdom of its direction under Mr Bush.

The practical implications of a Democratic win will matter less than the symbolic value. Democrats will surely push for some of their favourite legislative goals and will presumably hound Mr Bush and his senior officials over the conduct of the Iraq war.

But in some ways having to confront a hostile Congress helps a president — as it did Bill Clinton after 1994 and Mr Bush himself in 2002. Indeed, Republican hopes of winning the 2008 presidential election will surely be enhanced by a Democratic Congress for the next two years — when things go wrong it will not be so easy to condemn a “Republican Washington”.

It is what a large setback next week could do for Mr Bush’s legacy, however, for his governing and political style that could be truly devastating to his standing.

If Republicans go down in flames the chance of any candidate for 2008 taking up the Bush torch will be remote. Most presidential hopefuls, and indeed all but the most diehard Bush loyalists, will interpret the results as a stinging electoral rebuke, most obviously of the Iraq war and its conduct. Faced with electoral rejection, they will energetically distance themselves from it and the broader goals of an activist democracy-promoting foreign policy that Mr Bush has laid down. There will be criticism, too, within the party — already starting to be heard — of other aspects of his politics and governance, especially his curiously unconservative approach to government spending (more of it) and social policies such as immigration (much more of it).

Two years ago Mr Bush became the first president since his father to win more than 50 per cent of the popular vote. It looked then as though he had a good chance of recasting the Republican Party in his surprisingly radical image.

A big defeat for his party on Tuesday will demonstrate how short-lived that opportunity truly was.

WINNING RUN

1978

Unsuccessful Texan candidate for House of Representatives (47 per cent of the vote)

1994

Won Texas Governor race (54 per cent of the vote)

1998

Re-elected Governor of Texas (69 per cent of the vote)

2000

Elected US President (48 per cent of the vote)

2004

Re-elected US President (51 per cent of the vote)

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