As the Pennsylvania presidential primary approaches, both Democratic candidates are working hard for every vote. One particularly interesting demographic difference in the Obama-Clinton matchup relates to educational attainment. According to Gallup data, Barack Obama runs especially strong nationally among white Democrats with post-graduate educations (61 percent to 31 percent), while Hillary Clinton leads by nearly the same margin among those with a high school education or less. Obama’s support among whites with post-graduate educations rose by 10 percentage points following his March 18 speech on the Reverend Wright controversy (Obama’s support among whites with lower levels of formal education remained unchanged). Blacks of all education levels support Obama overwhelmingly. In a McCain-Obama matchup, Obama leads nationally among those with post-graduate educations, while McCain runs strong among those with high school educations or less. Source: The Gallup Organization, April 1-7, 2008.