Obama on the march

With less than a month to go in the marathon race for the US presidency, and Barack Obama forging ahead in most of the key states where the election will be decided, John McCain and his Republican allies are preparing a new round of deeply personal attacks on the Democratic front-runner in an attempt to seize back the initiative.

Struggling as the effects of the credit crunch and the deep unpopularity of President George Bush turn voters against him, Mr McCain plans to focus on "who Obama is", including questioning his character, "liberal" record and "too risky" proposals. His fitness to be America's commander in chief will be raised as the Arizona Senator seeks to shift on to ground more favourable to himself.

The new, more aggressive tone is likely to be on display as early as Tuesday night's second presidential debate in Nashville, Tennessee. Senior Republicans have long believed that Mr McCain's best chance of victory against his charismatic and organised opponent is to turn the election into a referendum on his character and readiness to occupy the Oval Office. "Turning negative" is seen as the last hope of turning the election around.

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Mr McCain dropped a broad hint of the coming turbulence at one of his "town hall meetings" in Colorado last week. Asked "When are you going to take the gloves off?", he cracked a broad grin and replied, "How about Tuesday night?" A senior Republican helpfully informed reporters that "we're going to get a little tougher". He was referring to a sharply negative television advertising campaign, which the Republicans hope will put a stop to the Obama campaign's gallop, just as Hillary Clinton did ahead of the Pennsylvania primary contest.

Back then it was Mr Obama's associations with his radical pastor, the Rev Jeremiah Wright, who had been filmed proclaiming "God damn America", that suddenly gave pause to millions of American voters. In April Mr McCain disassociated himself from attempts by the Republican Party in North Carolina to use the same charge in its advertising, but that now appears to have changed. Senior Republicans have revealed that a new advertising campaign will also attack Mr Obama for his links to the Chicago developer Antoin "Tony" Rezko, who was convicted of corruption.

One of the ugliest tactics is expected to be an effort to associate the Illinois Senator with terrorism because of his association with an unrepentant domestic terrorist from the 1960s. Republicans are pointing out that Mr Obama launched his political career in the home of Bill Ayers, who, with his wife, Bernadine Dohrn, was a former member of the Weather Underground movement, which killed several policeman during a bombing campaign four decades ago. Mr McCain will also argue that Mr Obama is dishonest on issues of taxation and warn that, if elected, his rival would bring dishonour to the US military by surrendering to terrorism abroad.

Mr McCain provided a foretaste of what was to come last spring. Referring directly to Mr Obama's links with Mr Ayers and Ms Dohrn, he asked: "How can you countenance someone who was engaged in bombing that could have, or did, kill innocent people?" Mr Ayers, now 63 and a respectable professor of education at the University of Illinois in Chicago, helped to found the Weather Underground in 1969. During the Days of Rage, at the height of the Vietnam War, it launched ineffectual bombing attacks on the Pentagon and Capitol Hill. Most were against institutions rather than people, but policemen's lives were lost.

Mr Ayers went on the run, but all charges against him were dropped in 1974 because of illegal wiretapping by the FBI. His memoir, Fugitive Days, opens with a quote from the author: "I don't regret setting bombs. I feel we didn't do enough." Mr Ayers now says his book was a condemnation of terrorism and indiscriminate murder of human beings, whether by fanatics or by government action.

His link to Mr Obama is that they are neighbours in Chicago's Hyde Park, and that in 1995 Mr Ayers hosted a coffee morning for him when he first announced his abortive bid for the US Congress. Mr Obama has since described Mr Ayers as "someone who engaged in detestable acts 40 years ago, when I was eight". But that distinction may be lost on US voters, who are as wary of terrorism today as they have ever been.

The attempted fightback would be characteristic of Mr McCain, who likes to remind supporters that he still has the instincts of "an old fighter pilot". His campaign has seen several surprises, such as his selection of the feisty but inexperienced Governor of Alaska, Sarah Palin, as his running mate, which boosted the Republican ticket sharply in the polls a month ago. That gamble was looking a little less reckless after last week's vice-presidential debate, in which Mrs Palin performed well enough to dispel the toe-curling memory of her interview with Katie Couric of CBS. But Mr McCain's latest manoeuvre – suspending his campaign and barging into delicate negotiations over the economy on Capitol Hill – failed spectacularly.

The Arizona Senator's campaign is in crisis, slipping behind in the polls as the crippled US economy turns large numbers of swing voters towards the Democrats. Now that President Bush has approved a historic rescue package costing taxpayers some $700bn (£380bn), the McCain campaign wants to switch the focus of every news cycle to doubts about Mr Obama.

The challenge for the Democrat is to keep reminding voters that the economic hard times are far from over, and that there will be no instant results, or even certainty that the rescue measures will work. The first buy-up by the US Treasury of the country's toxic assets linked to failing mortgages will not happen for at least six weeks, well after the 4 November election. When the candidates next meet they will debate the economy, Mr McCain's weakest suit. That clash comes as the Republican has pulled his campaign out of the battleground state of Michigan, with its rich haul of 17 electoral votes, in order to save money and resources for other crucial battles around the country.

The McCain campaign is on the defensive across many states that should have been safe bets for the Republicans. He is behind in Florida, North Carolina and Indiana. Even Virginia, which has been a conservative bedrock in presidential elections for the past 40 years, looks as if it has already fallen for the mesmerising spell of Senator Obama.

The campaign week

Sunday Bill Clinton pledges to do "all he can" to secure Obama's election. Fresh from a new skewering by Tina Fey on 'Saturday Night Live', Sarah Palin campaigns solo in Pennsylvania, contradicting John McCain's policy on Pakistan.

Monday McCain returns to the stump after a five-day "suspension" of his campaign to deal with the financial crisis. Palin goes into purdah to prepare for her debate with Joe Biden. The House upstages everyone by rejecting the bailout bill.

Tuesday Obama predicts a compromise on the measure, but McCain blames the failure on "excessive partisanship" by his opponent.

Wednesday New polls show Obama taking a clear lead in the key states of Florida, Ohio and Pennsylvania.

Thursday Palin's big day starts with a 'Washington Post' poll suggesting 60 per cent of Americans don't think she has the experience to step in as President. It ends with a better-than-expected performance against Biden.

Friday Morning-after reviews, however, make Biden the winner on points, for all Palin's perkiness. The House finally approves the bank rescue plan. But the government announces that the US lost 159,000 jobs in September.

Saturday As the presidential candidates prepare for their second debate, in Nashville, Tennessee on Tuesday, more polls show "swing states" leaning towards Obama.

Rupert Cornwell