Clinton Goes for Broke As Obama Rises in Polls

Hillary Clinton yesterday went back on the attack against her increasingly dominant rival for the Democratic presidential nomination, warning that the appeal of Barack Obama "dangerously oversimplifies the challenges we face".

Clinton questioned whether her opponent was being properly held to account by the media. She told a Christian TV network: "It is a disservice not to hold each of us to a very high standard because we are vying for the toughest job in the world." The attack was the latest illustration of the Clinton campaign's decision to unleash what an adviser told the New York Times was a "kitchen sink" fusillade against Obama.

On Monday Clinton gave a speech in which she derided Obama's lack of experience in foreign affairs, going so far as to compare him to President George Bush. "We've seen the tragic result of having a president who had neither the experience nor the wisdom to manage our foreign policy and safeguard our national security. We can't let that happen again," she said.

But such assaults, coming as the two candidates appeared on stage in the last scheduled televised debate in Cleveland last night, run the risk of looking like a desperate attempt on Clinton's part to keep her presidential hopes alive. A slew of new opinion polls show Obama extending his electoral grip among groups of voters until recently seen as her core supporters.

The surveys underline the critical few days facing Clinton, who must perform well in next Tuesday's primaries in Ohio and Texas if she is to stand any chance of regaining some of the momentum enjoyed by Obama, who has won 11 straight contests in the past two weeks.

A nationwide poll by Associated Press and Ipsos found that Obama had taken a significant lead among Democratic voters earning between $50,000 (£25,000) and $100,000 a year, reversing the lead Clinton had enjoyed among that group earlier this month. He has also pulled ahead among white men and those describing themselves as liberals.

A similar poll by the New York Times and CBS News found that even her prevalence among Democratic women voters has been eroded, with both candidates now standing neck and neck at 45%.

Obama received a further boost yesterday with the endorsement of the former presidential candidate Chris Dodd. The Connecticut senator's backing was seen as important partly because of his close ties with the Clintons, and because he is one of the 796 so-called super delegates to the Democratic National Convention.

On the Republican side, John McCain, the presumptive nominee, was quick to apologize to Obama after a controversial radio talk show host, Bill Cunningham, appearing at a McCain speaking event in Cincinnati, called Obama a "hack, Chicago-style Daley politician" and accused him of "sweetheart deals".