This
somewhat amusing editorial from the Philly Daily News reminded me that it's not just if you're registered, but what party you're registered with (hint: registering independent in this state is pointless) and also clued me in that it matters where you're registered. Some parts of the state count more than others, depending on how many people voted for Kerry in 2004 there. Quick internet research plus photoshop equals the handy graphic below (click for larger version).