* Biden was born in [[Pennsylvania]], a must-win state for Obama where he is weak;<ref>Hillary Clinton defeated Obama by a wide margin in the primary; in August polls show Obama leading McCain by an average of only 5.8% [http://www.realclearpolitics.com/epolls/2008/president/pa/pennsylvania_mccain_vs_obama-244.html RealClearPolitics Pennsylvania Tracking]</ref> however, Biden's roots are in the rural northeastern part of the state. | * Biden was born in [[Pennsylvania]], a must-win state for Obama where he is weak;<ref>Hillary Clinton defeated Obama by a wide margin in the primary; in August polls show Obama leading McCain by an average of only 5.8% [http://www.realclearpolitics.com/epolls/2008/president/pa/pennsylvania_mccain_vs_obama-244.html RealClearPolitics Pennsylvania Tracking]</ref> however, Biden's roots are in the rural northeastern part of the state. |