Democratic presidential candidate Barack Obama is moving within striking distance of rival Hillary Clinton in Pennsylvania, according to the latest Quinnipiac University Poll, out Tuesday.

Obama is now trailing Clinton — who weeks ago had a comfortable double-digit lead — 50 to 44 percent among likely voters surveyed in Pennsylvania from April 3-6. In a previous Quinnipiac Poll released April 2, Clinton was leading Obama 50 percent to 41 percent. The margin of error was 2.7 percent, meaning the poll does not show a statistical tie.

However, one of the most notable shifts, according to the poll, is among women — Clinton's stalwart base. In the latest survey, she leads Obama among women 54 to 41, compared to 54 to 37 percent in the April 2 poll. She is also dropping among white voters, where she leads Obama 56 percent to 38 percent, compared to 59 percent to 34 percent a week ago.

Obama is for the first time in the Quinnipiac poll doing better than Clinton among men, leading Clinton 48 percent to 44 percent, compared to a 46 percent to 46 percent tie on April 2.

"With two weeks to go, Sen. Barack Obama is knocking on the door of a major political upset in the Pennsylvania Democratic primary. Obama is building his own constituencies, but is taking away voters in Sen. Hillary Clinton's strongest areas — whites including women, voters in the key wing Philadelphia suburbs and those who say the economy is the most important issue in the campaign," said Clay F. Richards, assistant director of the Quinnipiac University Polling Institute.