(Agencies)
Updated: 2008-05-02 08:17

SOUTH BEND, Ind. -- Hillary Rodham Clinton was jolted Thursday by the defection of one of her longtime superdelegate supporters, a former national party chairman who urged fellow Democrats to "reject the old negative politics" and unify behind Barack Obama.

"A vote for Hillary Clinton is a vote to continue" a long, self-destructive Democratic campaign, Joe Andrew added in a letter designed to have an impact on the turbulent race nationally as well as in his home state of Indiana, site of a primary next week.

US Democratic presidential candidate Hillary Clinton addresses workers at the Duneland Falls Steelworkers Union Hall in April 2008 in Portage, Indiana. [Agencies]

"A vote to continue this process is a vote that assists John McCain," Andrew wrote.

In response, Clinton told ABC's "Nightline": "I think this has been good for the Democratic Party. ... People can decide however they want to decide. That's up to them. But anyone who believes this is bad for the party I just think is not paying attention, because the level of enthusiasm to be part of this process is, from my perspective, helping us build a stronger and deeper Democratic base."

Andrew's defection came at a particularly opportune time for Obama. The front-runner in the race, he has won more states than his rival as well as more of the popular vote, and he has an overall lead in delegates, 1736.5-1602.5. It takes 2,025 to clinch the nomination.

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But he has struggled in recent days to limit the political damage caused by controversial comments by his former pastor, the Rev. Jeremiah Wright.

Clinton's hopes of stalling Obama's drive to the nomination rest on a strong showing in the remaining primaries, beginning Tuesday in Indiana. At the same time, she hopes to persuade superdelegates that she would be a stronger candidate for the party this fall against McCain and the Republicans.

A top aide to the former first lady, Harold Ickes, sent a memo to superdelegates during the day making the case. Among the polls cited was a recent Associated Press-Ipsos survey that found Clinton leading McCain by 9 percentage points, while Obama was virtually tied with the Republican.

Andrew was one of five superdelegates to swing behind Obama during the day, compared to four Clinton netted. The result was to trim the former first lady's once-imposing advantage among party luminaries who will attend the convention to 268-248.

In his letter, Andrew not only challenged Clinton's claims about electability, but he also bluntly denounced the type of campaign tactics practiced by some in the Clinton circle.

"If the campaign's surrogates called Governor Bill Richardson, a respected former member of President Clinton's cabinet, a "Judas" for endorsing Senator Obama, we can all imagine how they will treat somebody like me," he wrote.

"They are the best practitioners of the old politics, so they will no doubt call me a traitor, an opportunist and a hypocrite. I will be branded as disloyal, power-hungry, but most importantly, they will use the exact words that Republicans used to attack me when I was defending President Clinton."

Andrew was far gentler on Clinton and her husband, both of whom he praised. But at one point, he wrote: "In an accident of timing, Indiana has been given the opportunity to truly make a difference. Hoosiers should grab that power and do what in their heart they know is right. They should reject the old negative politics and vote for true change."

Andrew made his move on a day in which Obama and Clinton campaigned across Indiana, where 72 convention delegates will be at stake. Polls point toward a close race in a state that even some of Clinton's supporters concede is critical to her campaign.

Clinton was joined by her mother, Dorothy Rodham, and her daughter, Chelsea, in Brownsburg, where she proposed allowing the federal and state governments to fund paid family leave. Her plan calls for a $3,000 tax credit to an individual with substantial long-term care needs or their caregivers as well as a tax credit to cover 75 percent of long-term care insurance premiums. She also favors expanding the Family and Medical Leave Act to cover workers at smaller firms.

Obama appeared before senior citizens as well as farm families on a day in which he continued to criticize Clinton and McCain for proposing a summertime suspension of the federal gasoline tax.

He said the average voter would save "a quarter and a nickel" a day, not enough to buy a cup of coffee at a convenience store, without making an appreciable impact on the nation's energy problems.

North Carolina, with 115 delegates at stake, shares the primary date with Indiana. Obama has long held a lead in North Carolina, in part because black voters are expected to account for as much as one-third of the ballots cast.

But a poll released during the day reported Clinton has closed the gap to single digits, and her campaign launched a television ad that features Gov. Mike Easley.

Former President Bill Clinton was in West Virginia on his wife's behalf. In Clarksburg, he called her a scrapper and contrasted her appeal among working-class voters with the elitists he said support Obama.

"The great divide in this country is not by race or even income, it's by those who think they are better than everyone else and think they should play by a different set of rules," he said. "In West Virginia and Arkansas, we know that when we see it."