President Obama now trails former Pennsylvania Senator Rick Santorum by four points in a hypothetical 2012 matchup in combined polling of key swing states Florida, North Carolina, Ohio and Virginia. The president continues to hold a modest lead in those states.

Santorum leads the president 48% to 44% in the so-called Core Four states. Five percent (5%) prefer some other candidate in this matchup, and two percent (2%) are undecided. This marks a shift from last week, when the president was slightly ahead of Santorum.