FORGET the staged smiles of last week’s televised debate between Hillary Clinton and Barack Obama at the home of the Oscars in Los Angeles. With two days to go before Super Tuesday, the contest for the Democratic presidential nomination has turned into a deadly struggle between two political titans.

Nearly half the country is up for grabs in one of the most evenly matched encounters of its kind. The crowds drawn by Barack Obama and Hillary Clinton to their rallies are so huge and the atmosphere so electric that it feels as if America is witnessing the final round of the battle for the White House rather than the preliminary skirmish to decide who will carry forward their party’s banner.

Accusations were flying thick and fast this weekend as the latest polls showed Obama rapidly gaining ground. Gallup’s daily national tracking poll put him just three points behind Clinton yesterday, compared with 11 points behind last Sunday. With Clinton still ahead in most of the biggest states voting this week, however, Obama was running out of time to wrest the mantle of history from his rival.

Tony McPeak, a former four-star air force general who is one of Obama’s advisers, took aim at Clinton’s performance in the New Hampshire primary last month, jeering that his candidate did not “go on television and have crying fits. He isn’t discovering his voice at the age of 60”.

A race like a crackpot Dynasty

The contest between Barack Obama and Hillary Clinton matches any fiction

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BACKGROUND

• The ascent of Barack Obama, Mr Charisma

• Decay, jobs and guns fall under the spotlight

• Free trade: Clinton/Obama's mistakes

The Obama camp apologised, but Clinton’s surrogates were just as quick on the draw. One of her advisers likened Obama supporters who challenged Clinton’s health care plans to “Nazis marching through Skokie, Illinois”. It was her campaign’s turn to say sorry for overreacting.

If the charismatic Obama, 46, was the first to demonstrate that he could fill a sports stadium when Oprah Winfrey, the television entertainer, joined forces with him in South Carolina last year, Clinton showed last week that she could attract thousands of cheering fans to the home of the Aztecs basketball team in San Diego, California.

“Wow,” she beamed. “This is unbelievable.”

Her supporters refused to be deflated by word that Winfrey was heading back on the campaign trail in California today with Obama’s wife, Michelle, 44, and Caroline Kennedy, 50, President John F Kennedy’s daughter.

“Oprah is a celebrity, but so what?” said Stacey Warnburg, 25, a legal secretary. “I know a lot of people like her, but she is not going to sway my opinion.”

In a sign of his growing confidence, Obama said he had promised his young daughters Melia, nine, and Sasha, six, a dog if he becomes president, although they are “not sure” if they want to move to the White House.

On closer inspection, the Aztecs’ stadium was not as full as it looked for Clinton. Half the hall was closed off by a black curtain. On the one side were 5,000 cheering supporters - 80% of whom were women, and 100% of whom were Democrats. The good news for Clinton is that her admirers are the rock-solid party loyalists most likely to vote on Tuesday.

The other, empty side could be said to represent the missing independents, disaffected Republicans and young first-time voters Obama is drawing to his 10,000-strong rallies - twice the size of hers - furthering his claim to be the best-placed candidate to take on John McCain, the Republican favourite, in a general election.

At one of his enormous rallies he declared that “I believe in the marketplace, I believe in capitalism” - words it is hard to imagine Clinton saying, no matter how centrist her politics.

As Democrats prepare to vote for their standard-bearer on Tuesday, they must decide whether to stick by Clinton, who has won their respect and affection but remains one of the most polarising figures in American politics, or “roll the dice”, as Bill Clinton put it, by choosing Obama, the candidate with the most promise, who has yet to prove that he can deliver.

Addressing the crowd, Hillary Clinton said it was thrilling that either she or Obama was going to “make history” as America’s first woman or first African-American president. For a long time, she had thought making history was her unique destiny. It was an admission that Obama might snatch the crown.

The giant state of California, previously a sure-fire win for Clinton, has suddenly become too close to call. It provides 441 of the 4,049 delegates whose job is to anoint the winner at the Democratic National Convention in August, but they could end up being fairly evenly divided after a Rasmussen poll showed her lead shrinking to three points.

In New Jersey, Obama is only six points behind Clinton, the senator for neighbouring New York. He appears to have been helped by the withdrawal of John Edwards, his rival for the votes of white men, from the race. In Connecticut, on the other side of New York, Obama has taken a four-point lead.

Clinton’s advisers can barely conceal their rage and bewilderment at Obama’s presumptuous challenge. They are seething at the way he has framed the race as a contest between the future and the past. “We do not believe that Senator Obama is ready to practice the politics of hope he talks about,” said Mark Penn, her chief strategist, through clenched teeth, after Obama suggested Clinton was a divisive figure. “He’s bringing out his greatest hits of negative attacks.”

Bill Clinton, who served as Hillary’s attack dog and chief race-baiter in South Carolina, where she lost heavily, has been muzzled after reminding voters too much of the downside of a Clinton co-presidency.

“Of course!” she was obliged to reply to the embarrassing question of whether she could control her husband. “If he did give offence, then I take responsibility and I apologise about that,” she said, swallowing her pride.

Yet it is never wise to write off the Clintons, who are at their most tenacious when fighting for their political lives. Robert Dallek, the historian, sees parallels with 1968, a time of disillusionment with the Vietnam War and political engagement by a new generation.

“This campaign is about calculation versus inspiration. Obama is riding the crest of a wave, but is he going to win?” Dallek asked. “I wouldn’t bet on it. The couple of days before Super Tuesday are going to be absolutely crucial. It could be that this race will end up being between Hillary Clinton and John McCain, just as in 1968 it ended up being between Hubert Humphrey and Richard Nixon, two of the oldest faces you can imagine on the political scene.”

Oddly enough, Obama’s greatest weakness may be his least expected. Some Democrats believe he is less likeable than Clinton, whom they have come to know. “Obama is arrogant,” said Duffy Fitzpatrick, 54, who brought her young son to see Clinton in San Diego. “My daughter was on his bandwagon until she really started watching him and decided that he was full of himself.”

It did not help when Obama appeared to snub Clinton in the Senate before President George W Bush’s State of Union Address last Monday. As she shook hands warmly with Senator Edward Kennedy, his highest-profile supporter, Obama turned his back on her.

Maureen Dowd, the witty columnist for The New York Times, believes Obama is in danger of appearing obnoxious. “You can see him get annoyed in real time, whereas Hillary is better at masking her emotions,” she said, observing him at a rally in Phoenix, Arizona.

Early in the campaign, Dowd suggested in an influential article that Michelle, his wife, seemed obsessed with putting him down, drawing attention to his inability to put his socks in the dirty laundry or make his bed – “a comic routine that rests on the presumption that we see him as a god”. Now she wonders whether Michelle knew something the rest of us did not.

“We may have to tell Michelle to get him down from his pedestal and go on about his socks again,” she said.

Obama is not a seductive figure like John F Kennedy, according to Dallek. “Kennedy was a man with a great deal of charm. Obama’s difficulty is that he comes across as an academic, a man who is very serious, even if he clearly can be quite inspirational.”

His greatest gift is to to talk about America’s problems, from the war in Iraq to the economy, in a manner that radiates optimism. “Who are our greatest presidents? George Washington, Abraham Lincoln, Franklin Delano Roosevelt, John F Kennedy and Ronald Reagan,” said Dallek. “It speaks volumes about people’s desire for hope and inspiration.”

Bit by bit, Obama has been cutting the ground from under Clinton, rolling out big-name endorsements with theatrical timing. The latest scion of a president to join his supporters’ club is Susan Eisenhower, granddaughter of “Ike”, who promised in yesterday’s Washington Post that “this lifelong Republican” would work for his election as “a man who can salve our national wounds and both inspire and pursue genuine bi-partisan cooperation”.

While rumours abound that Obama might snag the endorsement of Al Gore, the former vice-president and Nobel prize-winner, he has already got the better of the Clinton dynasty by winning the blessing of Ted Kennedy, 75, who is storming across California’s Hispanic community in support of Obama.

There were another 10,000 people at a rally last week for Obama in Arizona, where 17% of the population is Hispanic, yet whites and African-Americans dominated the crowd. Yolanda, a young parking attendant directing cars, said shyly that she was backing Clinton.

Inside, Abby Hansen, 45, a credit manager, described herself as a registered Republican. “I’ve had enough of the Clintons. I’ve never liked them.”

Obama, she said, could beat McCain, the senator for her home state, who, she believes, has never done much for Arizona. “I think we need somebody who is a step above. Obama seems very genuine,” she said.

Obama has struck at the heart of Clinton’s power by raising more money than her from a larger base of donors. In January, he received $32m (£16m), an astounding sum, while Clinton’s camp has remained silent about their fundraising totals.

Obama is already beginning to advertise in seven states beyond Super Tuesday where he believes he will have an edge over Clinton because of the strong presence of African-American voters and independents.

But Clinton is also proving that she can run an innovative campaign by staging the first “national town hall” meeting tomorrow evening – a rally linked by satellite to all 22 Super Tuesday states – and broadcasting it on the Hallmark channel, which specialises in films and kitchen-table dramas aimed at women.

The race appears to be so close that it may not be decided until March 4, when Ohio and Texas vote, or even April 22, when Pennsylvania finally has its say. Both camps are already wooing “superdelegates” – the 796 party notables who can vote as they please at the convention – in case neither candidate emerges with a strong lead.

Clinton has Bill and daughter Chelsea working the phones for her, but Bill’s power is diminishing after he failed to persuade Ted Kennedy to remain neutral.

Janet Napolitano, governor of Arizona, said she was dialling as many colleagues as possible on behalf of Obama. “I’m already on the phone talking to other delegates under the radar,” she said. “They tend to ask different questions from the voters about electability. One of the things I tell them is that he does very well among independent voters.”

Speculation is already growing about who Clinton or Obama would choose as vice-president to balance the ticket. Ted Strickland, the popular governor of the all-important swing state of Ohio, is an obvious pick for Clinton, while Evan Bayh, a senator and former governor of Indiana, which was lost to the Republicans in 2004, could be her second choice.

Some dream of a joint ticket with Clinton as president and Obama as vice-president. “I think Hillary and Obama would be the kiss of death for the Republicans,” said Jordan Stockberger, 20, a student at San Diego State University. “It would bring together all their supporters.”

In last week’s televised debate in Los Angeles – or love-in, as the pundits called it – Obama said that Clinton would be on anybody’s vice-presidential short-list. Clinton laughed appreciatively, but she is still hoping to “make history” without him. Additional reporting: Sara Hashash

The biggest day in the parties' nomination race

What is Super Tuesday?
This Tuesday, voters in 24 of the 50 states select delegates for the two parties' national conventions, where their presidential candidates will be officially chosen. Some 2,075 delegates from a total of 4,049 will be chosen by the Democrats and 1,081 delegates from a total of 2,380 will be chosen by the Republicans.

What is its significance?
It is the most important indicator of public opinion before the presidential election itself in November. Big states such as California will have their say. A decisive victory can win the nomination for a candidate. President George W Bush and Al Gore both won majorities on Super Tuesday in 2000 and then gained their parties' nominations. In 1992, Bill Clinton mounted a comeback on Super Tuesday and went on to serve eight years in the White House.

What are the rules?
They vary by state and between the parties. Most big states select their delegates in primary elections while many rural states use the caucus system of party meetings. Primaries will be held on Tuesday in 15 states, caucuses in the rest.

What makes Super Tuesday different?
Up to now the candidates have been engaged in 'retail' politics, where they can meet voters in diners or front rooms. They are now engaged in 'wholesale' politics where party organisation, advertising and soundbites come to the fore.

Isn't this a crazy way to choose a president?
On the contrary. It may be expensive and lengthy (Obama and Clinton raised more than $100m last year) but the candidates have to prove they have staying power, grit and the intellectual capacity to debate and campaign endlessly. It allows voters an opportunity to watch future leaders under pressure.

Video: Hillary Clinton speech at Laveen Arizona

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