John McCain and Barack Obama return to Pennsylvania today -- each for two-day swings in the state -- with Obama holding his largest lead in the state since Oct. 18, according to the newest Muhlenberg College/Morning Call tracking poll.

Why is McCain trailing? A look at the crosstabs on the poll makes it pretty clear: He's getting crushed among independents and is only getting support from three-quarters of Republicans. He's hitting west, central and eastern Pennsylvania today and tomorrow to try to close these margins, but this data can't have the McCain camp overly optimistic heading into the final week.

From the Muhlenberg College poll...



OVERALL

Obama: 53%

McCain: 40%



DEMOCRAT

Obama: 81%

McCain: 13%



REPUBLICAN

Obama: 18%

McCain: 74%



INDEPENDENT

Obama: 56%

McCain: 32%



MALE

Obama: 51%

McCain: 41%



FEMALE

Obama: 55%

McCain: 39%



CATHOLIC

Obama: 45%

McCain: 46%



PROTESTANT

Obama: 53%

McCain: 38%



WHITE

Obama: 49%

McCain: 43%



NON-WHITE

Obama: 90%

McCain: 8%

NO COLLEGE DEGREE

Obama: 48%

McCain: 41%



COLLEGE DEGREE

Obama: 59%

McCain: 37%



UNDER 60K

Obama: 50%

McCain: 43%



OVER 60K

Obama: 58%

McCain: 37%



SENIOR CITIZENS

Obama: 49%

McCain: 42%