A new public opinion poll shows Democrat Hillary Clinton's lead over rival Barack Obama in Pennsylvania is down slightly as both contenders campaign in advance of the primary there on April 22.  VOA National correspondent Jim Malone has the latest on the U.S. election campaign from Washington.

The new survey by Quinnipiac University in Connecticut shows Clinton with a nine-point lead over Obama in Pennsylvania.  That is down from a 12-point Clinton lead two weeks ago.

Clinton needs a victory in Pennsylvania to keep alive her hope of winning the Democratic nomination.

Both Democratic candidates are targeting more than 800,000 union members in Pennsylvania who are part of a critical voting bloc of working class voters.

Obama is warning against new trade deals that might hurt American workers while Clinton has proposed spending billions of dollars on tax incentives and investments to help companies create new jobs.

Clinton continues to insist she is in the race to stay despite Obama's lead in the delegate count.  During a campaign appearance in Philadelphia, Clinton compared herself to the fictional boxing hero of the film, Rocky.

"It is so important that the people of Pennsylvania have their voices heard and their votes counted," she said.  "Let me tell you something, when it comes to finishing the fight, Rocky and I have a lot in common.  I never quit, I never give up, and I know we are going to make it together.  We are going to climb that mountain for a better day for America."

While the latest Quinnipiac poll showed Clinton's lead being trimmed in Pennsylvania, the survey also seemed to buttress her argument that she would be the stronger Democrat in the general election campaign against the presumed Republican candidate, Senator John McCain.

Pollster Peter Brown tells VOA that Clinton runs stronger against McCain than Obama does in three key states.

"What is clear here is that, at least for now, Senator Clinton's argument that she is the better general election candidate appears to have some validity," he said.  "We poll Pennsylvania, Florida and Ohio, because no one has won the White House since 1960 without winning two of those three.  She runs much better that Senator Obama does against Senator McCain in each of those states."

Obama picked up two potentially helpful endorsements Wednesday.  Former Indiana Congressman Lee Hamilton, an experienced Democratic voice on foreign policy, threw his support to Obama, as did the governor of the western state of Wyoming, Dave Freudenthal.

Obama also said he would consider putting former Vice President Al Gore in a cabinet-level position or even higher if he is elected.  Obama said he talks to Gore on a regular basis about a range of issues including Gore's priority cause, global climate change.

During a question and answer session at a campaign event near Philadelphia, Obama also emphasized his differences over the war in Iraq with Senator McCain.

"The key to solving Iraq is political, not military, and that is why we have to send a clear signal to the Iraqi leadership that we are not going to be there maintaining permanent occupations," he said.  "John McCain has suggested we should.  That is a wrong approach, because it allows them just to continue to act irresponsibly."

For his part, McCain spoke at the U.S. Naval Academy in Maryland, recalling his days as a midshipman before embarking on a military career that included being held as a prisoner of war for five and one-half years in Vietnam.

McCain also told reporters that he has begun gathering a list of names of possible vice presidential running mates and that he hopes to announce his choice before the Republican nominating convention in early September.