President Barack Obama and his Republican challenger, Mitt Romney, are neck and neck in the race for the White House.
According to political analysts and observers, it's inevitable that such a fiercely contested election will go down to the wire because it reflects the same bitter divide in American politics and in society itself.
The political culture in America is now so polarised there is little, if any, social contact across the aisle in Congress, says lobbyist David Culp. "It's a random observation, but there used to be a lot more socialising of members," says Culp, who has 20 years of experience with the Friends Committee on National Legislation in Washington.
The split in Congress, where the Republican Party is in thrall to the ideologically extremist Tea Party, is now so severe that the Republicans have given up all pretence of bipartisanship. With a "fiscal cliff" looming over tax rises and spending cuts unless Congress acts, Democratic aides freely accuse the other side of putting politics before country.
On the eve of the 2010 midterm elections, in which the Republicans reclaimed control of the House for the first time in 40 years, the Senate minority leader, Mitch McConnell, pledged: "The single most important thing we want to achieve is for President Obama to be a one-term president." McConnell and the Republican Party, now described by conservative analyst Norman Ornstein as an "insurgent outlier", have never lost sight of that goal.
Ornstein teamed up with Brookings expert Thomas Mann to write a trenchant critique of the tribalism now afflicting American politics, in a book entitled It's Even Worse than it Looks. They unequivocally blame the Republican Party for the degradation of American political life. Ornstein told the New Zealand Herald that the resulting gridlock undermines democracy, because "the party with the reins of power has been delegitimised by half of its members". But he also noted that the partisan media, particularly Fox News, should also be blamed for contributing to the toxic atmosphere, in which "no lie is too extreme to be published".
American politics, because of the constitutional separation of powers to maintain checks and balances, have always been polarised. But Ornstein and Mann say it's never been this bad. They point out that political hostage-taking and "widespread denial of the elected president's legitimacy" have joined the Republicans' traditional arsenal of obstructionism.
The radical face of the party was on display again this week after Indiana Senate hopeful Richard Mourdock, a Tea Party-backed candidate, caused a furore during a campaign debate by saying if a woman falls pregnant after a rape, it is "something that God intended to happen."
Bill Bishop, the author of a 2008 book The Big Sort goes further. He points to a shifting American population where like-minded people move to the same post codes to live, think and vote near each other. "We move to get together with people with the same moral outlook and lifestyle. And that aligns with politics," he says.
So which came first, the toxic politics or the split within communities? Both, says Bishop, "one reinforces the other. A political scientist would tell you that political leaders are more extreme than the people they represent, but then the people are also more extreme."
With the rise of the Tea Party over the past couple of years, the run-up to the 2012 election has seen conservatives take up more extreme positions on the federal deficit and size and scope of government, in addition to the Republicans' traditional championing of lower taxes and their opposition to abortion. Bishop says that after 2008 there was a slight increase in geographical polarisation too.
Dante Chinni, the director of the Patchwork Nation project which maps communities across the United States, says: "It's the culture and the economics that are driving like-minded people to live near each other." Some people move for certain types of jobs. Wealthy Americans can simply choose to live in areas of like-minded people. There are neighbourhoods in Detroit, for example, whose residents are black, poor and vote Democrat. Fifty five kilometres west, in Ann Arbor, the residents are rich, white, and also vote Democrat. "The sorting is about lifestyle, not politics. But that lifestyle now is represented by political party," said Bishop.
Chinni predicted that the rural/urban divide would continue to grow in America. "Over the next 10 to 20 years, the rural locations will split."
Meanwhile, no one is saying the poison will drain out of the American political system after the November 7 election. Says Culp, "we are looking at very slim margins of victory in both the House and the Senate. That means the gridlock is going to get worse."
The Reuters/Ipsos poll says President Barack Obama leads by 53 per cent to 42 per cent among the 17 per cent of the surveyed registered voters who said they had cast their vote.
A new Time magazine poll in the crucial battleground state finds Obama holding a 49 per cent to 44 per cent lead.
Time says Obama also has a 60 per cent to 30 per cent lead over Mitt Romney among those who have voted early in the state.
Influence of the debates:
A Washington Post-ABC poll reports that 40 per cent of independents say their impressions of Romney improved over the debates while 18 per cent say their views deteriorated. For Obama, 20 per cent say their views deteriorated to 10 per cent improved.
The same poll found that among independents, 49 per cent believed that Romney was more empathetic on economic problems as opposed to 45 per cent for Obama. That's a change from earlier in the campaign cycle
The Washington Post reports that Obama and his backers have aired more ads in battleground states this month than Romney and his allies, despite being outspent by the Republican nominee and GOP groups. The Obama side spent US$77 million ($93.5 million) on 112,730 ads, according to the Wesleyan Media Project, which tracks and analyses political ad spending. The Romney side spent US$87 million on 97,730 ads.
The study said 915,000 ads had been shown during the general election campaign up until Monday - a 44.5 per cent increase compared with the same period four years ago.