US ELECTION: Neck and neck and at each other's throats, President George Bush and his Democratic challenger Senator John Kerry head for Tempe, Arizona, this evening for their third and final debate in the US presidential campaign.
The latest Gallup poll shows Mr Bush and Senator Kerry in a statistical dead heat, with the president trailing 49-48 per cent among likely voters, after leading by 10 points in late September in the same poll.
The decline to less than 50 per cent in approval ratings for the president - a red light for an incumbent - shows the impact on swing voters of the first two debates, in both of which voters declared Mr Kerry the winner.
The subject of tonight's 90-minute debate is domestic policy and sharp differences on issues that define the ideological and cultural divide in the US, such as abortion and stem-cell research, are likely to get an airing.
But Iraq and national security continued to dominate acrimonious long-distance exchanges yesterday as the two candidates campaigned for votes in the southwest.
Mr Bush, who still has a 17-point advantage on handling terrorism, ridiculed his rival for saying in an interview that America should return to a point "where terrorists are not the focus of our lives but they're a nuisance".
"I couldn't disagree more," the president told supporters in New Mexico. "Our goal is not to reduce terror to some acceptable level of nuisance. Our goal is to defeat terror by staying on the offensive."
The Democratic National Committee rushed out a TV ad showing Mr Bush in a recent interview admitting that the US could not win the war on terror.
The Kerry campaign also circulated a two-year-old comment from Brent Scowcroft, the national security adviser to former President George H W Bush, that the United States can break the back of terrorism "so that it is a horrible nuisance, and not a paralysing influence on our societies".
Senator Kerry attacked the president over soaring oil prices, which have hit particularly hard American voters who drive SUVs. The record price of oil "means a lot more profit for this president's friends in the oil industry, but for most middle class Americans, the Bush tax increase is a tax increase that they can't afford", he said.
Mr Kerry's accusation that Mr Bush is covertly raising taxes through record-high petrol prices is designed to blunt the new attack strategy from the Republican campaign - to hammer home the idea that Mr Kerry is a tax and spend Massachusetts liberal, out of touch with mainstream America.
The president has reworked his campaign speech twice in recent days to confront Mr Kerry on issues where the Democrat has won high approval ratings in the debates.
Recalling that his rival said in Missouri on Friday that he would not raise taxes for people earning under $200,000 a year, Mr Bush said to do that "he would have to break all his other promises" or "he's going to have to raise your taxes".
As the November 2nd polling day approaches, Mr Bush is appealing more to his conservative base, and his opposition to abortion is likely to be an issue in tonight's confrontation.
The president is getting support on the issue from a group of Catholic bishops, led by Bishop Charles Chaput of Denver, who stops short of telling people to vote for Bush but reminds them of Mr Kerry's support for abortion rights. The group has reportedly spent four years recruiting 50,000 volunteers to encourage a turnout of Catholic voters, according to the New York Times.
Other bishops, including Archbishop Raymond Burke of St Louis, Bishop Michael Sheridan of Colorado and Bishop John Myers of Newark, have warned Catholics that the obligation to oppose abortion outweighs any other issue. Mr Kerry, who is a Catholic, said in the debate in Cleveland last week that he cannot take an article of faith for himself and legislate it for someone with a different faith.
Mr Bush also has the approval of religious conservatives for his opposition to federal funding for stem-cell research, on the ground that embryo tissues are used, but on this issue Mr Kerry has broad public support.
The actor Christopher Reeves, who died on Monday and who was a heroic figure in the US for his struggle against paralysis, sent the Democratic candidate a message on Saturday to keep up the fight for stem-cell research.
The Gallup poll, conducted for USA Today and CNN, shows voters increasingly pessimistic about the economy, the war in Iraq and the battle against terrorism and it also confirmed that a large majority of voters believe Kerry did better than Bush in their second debate.
Taken on Saturday and Sunday, the poll puts Kerry at 49 per cent and Bush at 48 per cent among likely voters with independent candidate Ralph Nader at one per cent. Among all registered voters, Kerry and Bush each had 48 per cent.
In the 17 states that both campaigns see as most competitive, Kerry was at 48 per cent and Bush at 45 per cent, leading the Democrats' pollster Mark Mellman to say: "We see very strong momentum to John Kerry nationally, particularly in the battleground states."
Bush strategist Matthew Dowd said growing concern about terrorism, Iraq and the economy hadn't boosted voters' trust in Kerry to handle those issues.
While Mr Bush has a 17-point lead on terrorism and is ahead seven points on Iraq, Senator Kerry is preferred on most domestic issues.
He is in front by 29 points on the environment, 19 points on health care and 13 points on the federal budget deficit.