The latest polling in Pennsylvania's 8th Congressional District from Monmouth University shows former Congressman Michael Fitzpatrick in the lead against Democrat Patrick Murphy, 51 percent to 46 percent.

The 8th District is basically Bucks County, to the north of Philadelphia, with a small, heavily Democratic salient into Montgomery County.  The political demography of Bucks is summarized nicely by this map:

The southeastern portion of the county -- some of the original suburban developments in the nation -- is heavily Democratic.  As you move further to the northwest, the county gradually becomes more Republican, and less densely populated.  Thus, both parties have a substantial base upon which to draw.

But this year, the Republican portion of the district seems much more enthused.  Even though President Obama carried it by nine points in 2008, only 40 percent approve of the job he is doing today.  Monmouth finds overall voter registration in the district to be 45 percent Republican and 42 percent Democrat, which is actually pretty close to the numbers for Bucks County as a whole.  Three weeks out, it looks as though Patrick Murphy has a tough sell for re-election.

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