YOUNGSTOWN (Ohio) - DEMOCRAT Barack Obama and Republican rival John McCain take their White House duel deep into the American heartland on Friday in a final push for votes ahead of next week's historic election.
With just four days left before Tuesday's presidential ballot, front-runner Obama was to hold campaign rallies in the midwestern states of Iowa and Indiana while Mr McCain was wrapping up a two-day bus tour of Ohio.
On Thursday, the two candidates traded body-blows after grim new figures showed the world's largest economy is staring at recession.
The US government said the economy had shrunk by 0.3 per cent in the third quarter through September, its worst contraction since 2001.
Mr McCain's campaign insisted the bleak economic outlook would be made even worse by an Obama administration, saying his opponent would raise taxes on small businesses and so stifle growth and kill jobs.
'Today's announcement ... confirms what Americans already knew: the economy is shrinking,' Mr McCain adviser Doug Holtz-Eakin said in a statement.
'Barack Obama would accelerate this dangerous course.'
But Mr Obama, 47, bidding to become the first black US president, pounced on the news to say his rival would pursue what he called failed Republican policies promulgated by President George W. Bush.
'If you want to know where John McCain will drive this economy, just look in the rear-view mirror. Because when it comes to our economic policies, John McCain has been right next to George Bush,' Mr Obama said.
'He's been sitting there in the passenger seat, ready to take over, every step of the way,' he told a crowd of more than 60,000 supporters on a day-long blitz though the battleground states of Florida, Virginia and Missouri.
'It is time to change drivers. It is time to have somebody else at the wheel.'
In an interview with NBC News, Mr Obama said the job facing the president-elect taking office on January 20 had gotten much harder as a result of the financial crisis.
'It's going to be a lot tougher. I don't think there's any doubt about that. We know that the next president is likely to inherit a significant recession,' Mr Obama said, while sticking to his list of big-spending priorities.
Mr McCain, 72, has struggled to compete with Mr Obama on economic policy as polls show the issue remains the overwhelming concern for voters.
The latest national poll by the New York Times and CBS News gave Obama a yawning lead of 11 points among likely voters - 52 per cent to 41 for Mr McCain.
It also suggested that McCain's pick of Alaska Governor Sarah Palin as his vice-presidential running mate might be dragging on his campaign.
Fifty-nine per cent of voters surveyed thought the Palin was not prepared for the job of vice-president and 41 per cent of respondents had an unfavorable opinion of her, compared with 36 per cent who had a favourable opinion.
On Thursday, Mr McCain wheeled out Ohio tradesman Samuel J. Wurzelbacher, better known as 'Joe the Plumber', to buttress his case in a state that he must win if he is to take the White House.
No US president has been elected without winning Ohio since 1960, and Mr Obama is ahead in state polls.
Mr McCain was to call on former movie star turned California Governor Arnold Schwarzenegger to campaign alongside him in Ohio on Friday, before heading to Pennsylvania.
Mr Obama was enlisting former vice president Al Gore to campaign for him in Florida, where the anti-global warming crusader suffered his agonising loss in the 2000 election to Bush.
After his Iowa event, the Democrat was to break for a Halloween visit to his two young daughters in Chicago before heading to an evening rally in Highland, Indiana, just over the Illinois border.
Mr Obama has a decisive polling lead in Iowa, which was won by Bush last time.
Conservative Indiana has rarely been friendly territory to Democratic presidential aspirants, but Mr McCain is barely ahead in polls there.
The Democrat's vice-presidential running mate, Mr Joseph Biden, is using the seasonal festivities to hammer Mr McCain's portrayal of himself as a 'maverick' who is out of step with the unpopular president.
'I know that Halloween is just around the corner. But folks, Mr John McCain dressed as an agent of change, that costume just doesn't fit,' Biden said late Wednesday at a joint rally with Mr Obama in Florida.
'Not when he's bragged about voting with George W. Bush 90 percent of the time.'
