John McCain is signalling another abrupt change of course for the final three weeks of the campaign since his haphazard response to the financial crisis and faltering attacks on Barack Obama's character have given the Republican the appearance of being desperate, in disarray, or even dangerous.

Yesterday he was locked in talks with economic advisers trying to come up with a coherent package of proposals for stabilising markets to present in this week's final debate against his Democratic rival.

Last week's campaign effort — largely led by his running mate Sarah Palin — to switch focus away from the economy by highlighting Mr Obama's Chicago links with Bill Ayers, a former domestic terrorist, is seen as having backfired with independent voters.

Video clips show crowds at McCain-Palin rallies taking up the theme to scream “treason!” or “terrorist!” at the mention of Mr Obama's name, or still more sinisterly, “kill him!” and “off with his head!”. Mr McCain has been forced to appeal for calm, rebuking a man who said he was afraid of raising his child under Mr Obama. The Republican nominee said to boos from a crowd on Friday: “I have to tell you he is a decent person and a person that you do not have to be scared of as president.” He snatched the microphone later from a woman who suggested Mr Obama was an Arab.

On Saturday the civil rights leader and congressman John Lewis likened the atmosphere at Republican rallies to those of George Wallace, the segregationist former presidential candidate, saying: “Senator McCain and Governor Palin are sowing the seeds of hatred and division.” Mr McCain responded by expressing sadness that “a man I've always admired would make such a brazen and baseless attack”.

At a weekend event in Iowa, Mr McCain's campaign swiftly repudiated a pastor who introduced him with the claim that millions of foreigners were praying to “Hindu, Buddha, Allah — that his opponent wins”.

Many Republicans now openly acknowledge that his campaign has been adrift in recent weeks, ill-suited to deal with the economic storms or carry the increasingly heavy baggage of Mrs Palin. An inquiry on Friday concluded that she had abused her powers as Alaska Governor by trying to orchestrate the sacking of a state trooper who was her former brother-in-law.

Some suggest the problems began when — under pressure from conservatives — he picked her as vice-presidential nominee ahead of Joe Lieberman, an independent Democratic senator who would have reinforced Mr McCain's claim that his rival was too inexperienced for the White House.

One senior strategist suggested the decision was part of a pattern in which Mr McCain had damaged his reputation as a straight-talking free-thinker by courting a Republican base in the nomination battle. But friends say Mr McCain has been stung by suggestions that his attacks on Mr Obama are reminiscent of the smear tactics that halted his run for the White House eight years ago when he was beaten by George Bush. They point out how he has resisted pressure from his own campaign to raise the racially incendiary sermons of the Rev Jeremiah Wright, Mr Obama's former pastor.

Indeed, with polls pointing to defeat, there is suspicion that Mr McCain may now be most concerned about restoring some lustre to his tainted brand. At the weekend he was forced to answer appeals to be tougher on Mr Obama by insisting he still cared about the election's outcome. “Believe me, I am motivated,” he said.

Twists and turns

— June 4, 2008 Calls for ten town hall meetings with Obama to embrace “the politics of civility”; repeatedly contrasts his “experience and judgment” with Obama's youth

— July 30 Launches advertising campaign portraying Obama as “the biggest celebrity in the world”

— August 29 Picks the inexperienced Sarah Palin as his running mate

— September 24 Announces suspension of campaign and calls for cancellation of first debate so he can return to Washington to resolve financial crisis

— September 26 Leaves Washington, resumes campaign and goes to debate

— October 6 Begins aggresssive attacks on Obama over his links with Bill Ayers, a former terrorist

— October 10 Denounces attacks on Obama's character and calls his rival “a decent family man”

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