i don't completely understand why pennsylvania is considered to be a "swing state." sure, it's always seems close here leading up to the election. PA may swing in the pre-election polls (though that's not what is happening this time), but in the end it always seems to end up blue.
at least that's how it has worked in recent elections. you have to go back twenty years to find the last time that this state gave its electoral votes to a republican. but in those days the republicans were the party that was assigned the color blue on the electoral map.
