Has the tide turned against Clinton?

She once looked to have an invincible lead over her Democratic rivals, but the former First Lady has had to call in all the family to boost her flagging campaign

Senator Hillary Clinton is battling to contain a deepening crisis in her presidential bid amid evidence that her closest rival, Barack Obama, is riding a late surge of support in the two critical states that kick off the party nominating process in the new year, Iowa and New Hampshire.

With less than three weeks before the first votes are cast, there are new signs that the tide may be turning against the former First Lady. She has seen her once impressive lead in both states evaporate in several new polls, while her message has been overwhelmed by headline-making stumbles by her campaign team. It is a startling reversal for Mrs Clinton, who until recently had successfully cultivated an air of invincibility about her campaign.

Mrs Clinton took off yesterday on a desperate helicopter dash across Iowa to woo back her wavering voters. Looking to appeal especially to women, she has also launched new television advertising spots in the state featuring her daughter, Chelsea, and her 88-year-old mother, Dorothy Rodham.

That she may be in trouble has not escaped her, however. "If I had listened to the Washington class, I would not be standing here, would I?" she told reporters before beginning her latest Iowa tour. "I believe in trusting my own instincts. I feel very, very good about the case I am making."

The Clinton campaign was blind-sided last week when her party manager in New Hampshire, Bill Sheehan, raised confessions by Mr Obama of past drug use while a young man, and went so far to ask whether he had possibly been a dealer. He resigned after his remarks sparked a storm of opprobrium and Mrs Clinton found herself having to apologise to her rival on the tarmac of Washington DC's main airport.

Solace in Hillaryland as her campaign is sometimes called can still be found in national opinion polls which show that Mrs Clinton maintains a gaping lead over both Mr Obama and her other main rival, John Edwards. Indeed, the national surveys have been more or less static for several months.

In Iowa, however, which will hold caucus voting for both the Democratic and Republican parties on 3 January, Mrs Clinton has slipped into a statistical dead heat with both Obama and Edwards. In New Hampshire, where the primaries come just five days later, her loss of ground seems to be even greater. Once comfortably ahead, she is shown in one poll to be two points behind Mr Obama.

Losses in both Iowa and New Hampshire, while they would not necessarily be fatal for the Clinton candidacy, would certainly shatter the myth of her invincibility. Her rivals, by contrast, would similarly receive a huge boost.

Even Bill Clinton, the former president who has helped draw crowds for his wife on the stump in both states, is now playing the game of lowering expectations. In a late Friday night television interview with Charlie Rose on the PBS channel, he said that "it's a miracle that she's got a chance to win" in Iowa.

The troubles for Mrs Clinton began at a televised debate on 30 October in Philadelphia when she fumbled several answers, particularly about a now-abandoned plan in New York to give driving licences to illegal immigrants. Sensing the first chinks in her armour, the other contenders quickly pounced.

In response, she has grown sharply more critical of her rivals a risky tactic, particularly in Iowa, where voters traditionally are turned off by negative campaigning. She appears to have been hurt, for instance, by a press release highlighting a kindergarten essay by Mr Obama entitled "I want to Become President". It was meant to show him as consumed by ambition, but voters didn't like the tactic.

"The only way to stop these kinds of tired, desperate attacks is to demonstrate very clearly that they have a real cost to Senator Clinton's campaign," Mr Obama's campaign manager said in a fund-raising letter sent out on Thursday