The long and increasingly negative battle between Barack Obama and Hillary Clinton appears to have taken a heavy toll on the reputation of the former First Lady, with her false claim to have dodged sniper fire in Bosnia in 1996 emerging as one of the biggest blunders of the campaign.

Polls released yesterday revealed that Mrs Clinton has lost the trust of US voters and that more Americans now view her unfavourably than at any time since she entered the White House as First Lady in 1992.

In a worrying sign for Mr Obama, despite a new survey showing him to be the favoured candidate among Democrats to become their presidential election nominee, nearly half believe that recent revelations about his former pastor’s incendiary comments could doom him in a November contest against John McCain, the Republican nominee-apparent.

With just six days until the next nominating contest for the Democrats, in Pennsylvania, Mr Obama will nevertheless be encouraged by the polls yesterday. They suggest that he is weathering the controversy over his remarks that blue-collar voters “cling” to guns and religion because of their straitened circumstances.

A race like a crackpot Dynasty

The contest between Barack Obama and Hillary Clinton matches any fiction

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• Decay, jobs and guns fall under the spotlight

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Mrs Clinton, who held double-digit leads over Mr Obama in Pennsylvania last month, was ahead by 46 per cent to 40 according to the Franklin & Marshall College poll in the state. The same poll found her ahead by 16 points in March. Other polls showed Mr Obama leading in Indiana (by 5 points) and North Carolina (by 13 per cent) — the next states to vote on May 6, after the contest in Pennsylvania on Tuesday.

Mr Obama also received a boost before the primary next week with two significant endorsements. The Pittsburgh Post-Gazette, in a part of the state that favours Mrs Clinton demographically, backed her rival.

The Illinois senator was also backed by Bruce Springsteen, the veteran singer. It was a well-timed endorsement in the light of claims by Mrs Clinton that the remarks of Mr Obama showed him to be elitist and condescending to America’s workers. The music of Springsteen, who has sold more than 65 million albums in the US alone, includes anthems celebrating the American working man.

A survey by The Washington Post and ABC News showed that Mr Obama holds a ten-point lead over Mrs Clinton among Democrats asked whom they would prefer to see as the party’s nominee. In the poll, 54 per cent of Americans said that they had an unfavourable view of Mrs Clinton, her highest “negatives” since the question was first asked about her 16 years ago. It is up from 40 per cent just after she won the New Hampshire primary in January. Just 39 per cent believe that she is honest and trustworthy, the poll showed.

The favourability rating for Mr Obama has also dropped, from 63 to 56, but his negative rating is far lower than Mrs Clinton’s, at 39 per cent. Twice as many Democrats saw him as more electable than Mrs Clinton, a sharp reversal of earlier trends.

Overall, the polls suggest that the false claim by Mrs Clinton that she ducked sniper fire on a visit to Bosnia has damaged her more than the comments from Mr Obama have damaged him. Republicans are already highlighting the comments as proof that Mr Obama is a liberal elitist, one of their most effective strategies against Democratic presidential candidates.

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