Obama Gaining on Clinton Lead in PA.

AP Sen. Barack Obama was endorsed Wednesday by a labor union and two Democratic superdelegates, as a poll showed he has cut Sen. Hillary Rodham Clinton's lead in Pennsylvania almost in half since mid-February as he strives to deny her a resounding victory in the state's presidential primary.

The Illinois senator peeled off an affiliate of the American Federation of State, County and Municipal Employees, which has endorsed Clinton. The Philadelphia-based local of the National Union of Hospital and Health Care Employees has about 16,000 members.

Its president, Henry Nicholas, announced the endorsement while introducing Obama at a meeting of the Pennsylvania AFL-CIO.

Nicholas, who also is president of the 150,000-member national union and an AFSCME international vice president, said he took the step "because justice told me it was the right position to take."

Meanwhile, Wyoming Gov. Dave Freudenthal and former Montana Sen. John Melcher endorsed Obama. As superdelegates to the national convention, they are among the Democratic Party leaders who will decide the nomination because, although Obama leads Clinton in delegates, neither candidate can win solely with pledged delegates they've won through primaries and caucuses. Obama handily won Wyoming's March 8 caucus; Montana holds a Democratic primary June 3.

Since last Friday, Obama has cut Clinton's lead among superdelegates by four; she has 250 to his 220.

Asked on MSNBC's "Hardball" about the possibility he could finish the primary season with a lead among delegates but still not get the nomination, Obama said it was too early to worry about that.

"Most of the superdelegates who have not yet decided, I think will recognize that we've earned this nomination. That's not guaranteed and I don't take anything for granted," Obama said. "I'll let the poobahs of the party make a decision as to how they want to deal with it."

As Obama and Clinton campaigned in Pennsylvania, where the primary is April 22, a new poll showed him cutting into her lead by drawing more support from men and young voters. Clinton's 16-percentage-point lead in mid-February slid to 12 points in mid-March and now to nine points, according to the Quinnipiac University telephone poll, which ended March 31.

Clinton is well ahead of Obama among Pennsylvania's white voters, 59 percent to 34 percent, while he gets nearly three of four black votes. She is well ahead among women, while the two are even with men.

With both candidates wooing union members, displaced workers and anxious families, they quarreled again over which of them would oppose or modify trade deals such as the North America Free Trade Agreement. Some labor leaders blame NAFTA for sending U.S. jobs overseas, a claim that many economists dispute.

As many as 830,000 union voters are expected to have a strong say in how more than 4.1 million Democrats, a record registration for Pennsylvania, allocate the state's 158 delegates to the Democratic national convention.

Obama told the AFL-CIO gathering that he will oppose pacts that threaten U.S. jobs.

"What I refuse to accept is that we have to sign trade deals like the South Korea Agreement that are bad for American workers," Obama said.

Speaking to the same unions a day earlier, Clinton said as first lady she had forcefully battled the agreement President Clinton labored hard to win.

"I did speak out and oppose NAFTA," she said. "I raised a big yellow flag and said, 'I don't think this will work.'"

Teamsters president James P. Hoffa, who is backing Obama, disputed her claim.

"No one who was around in the time of NAFTA remembers her doing that," Hoffa told The Associated Press during a telephone interview. "Let's face it, she's tied to NAFTA no matter what she says."

At an economic summit in Pittsburgh organized by her presidential campaign, Clinton said she would eliminate tax breaks for companies that move jobs to other countries and use the savings to persuade them to keep jobs in the U.S.

Clinton's plan would offer new tax benefits for research and job development. It would also create "innovation and research clusters" across the country and provide $500 million annually in investments to encourage the creation of high-wage jobs in clean energy.

Clinton called it her "insourcing agenda."

"We hear so much about outsourcing," when jobs are lost to other countries, she said. "I want to put an end to it. We're going to change the tax code, we're going to change the giveaways to the special interests."

Clinton also broadcast a new TV ad in Pennsylvania explicitly challenging Republican John McCain's economic credentials.

Echoing an earlier ad aimed at Obama on national security, it begins with images of sleeping children while a narrator says a phone is ringing in the White House at 3 a.m. but this time the crisis is economic. As the phone rings on and on, the sleeping children are replaced by adults grimly reviewing bills during daylight hours. The narrator faults McCain's response to rising home foreclosures and teetering markets and says he'd just let the phone keep ringing. The ad ends with an image of Clinton answering a phone.

The latest Associated Press tally of delegates shows Obama leading Clinton 1,634 to 1,500. The count includes superdelegates party leaders and elected officials who are free to vote for whichever candidate they wish regardless of primary and caucus outcomes although Clinton leads in those votes 250 to his 220.