As the race for the White House between Democrat Barack Obama and Republican John McCain appeared to be tightening four days before election, the rival campaigns narrowed their focus to four battleground states.
Racing to 13 rallies across Ohio, Florida, Virginia and Missouri the rivals on Thursday hammered their economic messages as a new CNN poll of polls showed Obama's lead over McCain narrowing to 5 points nationwide, 49-44 per cent.
The gap between the two is now 3 points less than it was earlier this week, and nearly half what the margin was one week ago, CNN said.
The Republicans are warning of widespread tax increases if the Democrats win the presidency and wide majorities in Congress. The Democrats say their rivals will prop up corporations and the rich but ignore the struggling middle class.
The closing of polls late in a presidential race is not unusual, CNN said noting Democrat John Kerry lost his 2004 White House bid despite holding a slim lead over President George Bush in its final days and then Vice President Al Gore trailed Bush by 5 points in early November before the two essentially split the vote days later.
"It's possible that McCain will continue to close the gap over the final few days of the campaign," said CNN Senior Political Researcher Alan Silverleib. "Presidential elections often tighten up at the end, especially if there's not an incumbent on the ballot. Voters sometimes experience a degree of 'buyer's remorse' before settling on a new president."
Historically, however, only one presidential candidate in modern history has come back from the deficit McCain faces to win an election - Ronad Reagan in 1980, it said.
Meanwhile, according to the latest New York Times/CBS News poll a growing number of voters have concluded that McCain's running mate, Governor Sarah Palin of Alaska, is not qualified to be vice president, weighing down the Republican ticket in the last days of the campaign.
All told, 59 percent of voters surveyed said that Palin was not prepared for the job, up 9 percentage points since the beginning of the month. Nearly a third of voters polled said that the vice-presidential selection would be a major factor influencing their vote for president, and those voters broadly favoured Obama.
In a possible indication that the choice of Palin has hurt McCain's image, voters said that they had much more confidence in Obama to pick qualified people to serve in his administration than they did in McCain.
The New York Times poll also found Obama maintaining his lead, with 51 per cent of likely voters supporting him and 40 per cent supporting McCain in a head-to-head matchup.
Some perceptions of race are changing, with a marked increase in the number of people who say they believe that white and black people have an equal chance of getting ahead in America on Friday, the Times said.
While McCain has enlisted the help of Joe the Plumber, otherwise known as Samuel J. Wurzelbacher, since Obama told him he wanted to "spread the wealth", the Democrat has turned to the party's two rock stars in the closing days of the campaign, former President Bill Clinton and former Vice President Al Gore.
On Thursday, Wurzelbacher made a last-minute appearance at a rally in Elyria, Ohio, after missing an earlier campaign appearance.
As for Obama, he made his first joint campaign appearance with Clinton in Kissimmee, Florida on Wednesday night. Gore and his wife, Tipper, plan to campaign for Obama in that state on Friday.