The Politico reported Tuesday that the Illinois senator's poll numbers in Pennsylvania have not declined since an audio tape emerged of Obama saying that small town voters are "bitter" about their economic situation and "cling to guns or religion or antipathy to people who aren't like them or anti-immigrant sentiment."

The Quinnipiac University poll found that Sen Hillary Clinton, D-N.Y., leads Obama 50 to 44 percent, a margin unchanged since the beginning of the month.

The poll, conducted Wednesday through Sunday night, comes ahead of the Keystone State's pivotal primary April 22.

The Quinnipiac poll of 2,103 likely Democratic primary voters also found that 26 percent of Clinton supporters would back Republican presidential hopeful John McCain if Obama won the Democratic nomination, while 19 percent of Obama's supporters would switch to McCain if Clinton was the nominee.

The poll had a margin of error of plus or minus 2.1 percentage points.