Hillary Clinton, in South Boston yesterday to continue her efforts to unite the Democratic Party, urged thousands of letter carriers who had been early and enthusiastic backers of her campaign to throw their support behind Barack Obama, her former rival and now the presumptive nominee.

Clinton told nearly 10,000 members of the National Association of Letter Carriers, gathered at the Boston Convention and Exhibition Center for their biennial convention, that electing Obama would mean expanding healthcare access, preventing further outsourcing of government jobs, and improving the lives of working people across the country.

"The best way to stand up for everyone who feels invisible is to make sure we have a Democratic president taking the oath of office on Jan. 20, 2009," she said.

The NALC, which claims about 300,000 active and retired members, is one of many large labor unions that supported Clinton during the long and sometimes bitterly contested nomination contest that ended in early June, when Clinton dropped out and endorsed Obama. Nearly a month ago, the two former rivals held a highly choreographed rally in Unity, N.H., to urge the Democrats to join forces to beat John McCain, the presumptive GOP nominee.

Since then, Clinton has appeared at a pair of Obama fund-raisers in New York City and aides said her calendar is quickly filling with other events. She has also brought her unity message to the American Federation of Teachers convention and the League of United Latin American Citizens convention earlier this month.

But polls indicate the former rivals still have work to do in energizing the party. An Associated Press-Yahoo News poll released this month found that just 12 percent of former Clinton supporters were excited about the campaign, even though Obama's supporters were generally much more energized than McCain's.

Awkwardness over finances also still exists. Campaign finance records show Clinton loaned her campaign another $1 million last month, bringing her total personal loans to her campaign to $13.2 million, and she still owes vendors another $12 million. Obama has asked his top donors to help Clinton pay down her debts, but it doesn't appear to be helping: The campaign received only $2.7 million in June.

Her appearance yesterday was suffused with nostalgia. The union presented Clinton with a sentimental video of her on the campaign trail and unanimously voted to make her an honorary union member. She accepted, inviting members to flag her down if they ever need a helping hand along their routes. But she never lost sight of her message.

Among those cheering were Lucy James and Leslie Hammett, both Democratic letter carriers in their 50s from Las Vegas who had worked for Clinton's campaign in Nevada. "I've got foreclosed houses all over my route," said Hammett. " 'For Sale' signs - it's like a forest of them. They're losing their jobs, they're losing their homes."

Others were unmoved by Clinton's speech. Gary Griffis, a 59-year-old Republican from Cincinnati, kept quiet when the rest of the members endorsed Obama yesterday because he didn't want to be rude. But he said he plans to vote for McCain in November because he feels Obama is ill prepared to be president. "I think the security of this country is far greater than my job," he said.

By Lisa Wangsness, The Boston Globe, July 22, 2008