Our Vote Live.org is tracking voting problems being reported during the November 4th, 2008 election and has several maps showing where the problems are occurring, both at the state and county level. .  
The maps below are from 11:30 AM EST, but already show that there are a lot of voting issues accross the country. [...]

The New York Times examines the challenges facing Barack Obama in Pennsylvania, a state won by both Gore in 2000 and Kerry in 2004.
To roam the rural reaches of western Pennsylvania, through largely white working-class counties, is to understand the breadth of the challenge facing the two presidential candidates. But this economically ravaged region, once so [...]

The next post in Real Clear Politics series on key swing states examines Pennsylvania, which has voted Democratic since 1992, but has been listed by both the Obama and McCain campaigns as a potential swing state in this election.

Swing State Review: Pennsylvania

what McCain must do to flip Pennsylvania from blue to red. There are four [...]

All eyes are on Pennsylvania as voters go to the polls to cast the first ballots in the Democratic presidential primary in nearly six weeks. News and Maps in the links below. Be sure to check back, as this page will be updated through out the day and night as more news breaks and election results come in.
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- New York Times: Pennsylvania Primary Map
- 538: Pennsylvania Scorecard
- Washington Post: Pennsylvania Political Geography
- The Electoral Map: Pennsylvania Primary Predictions
- Cogitamus: More Pennsylvania Registration Maps

Looking for exit polls for Pennsylvania Democratic Primary exit polls?

* CNN
* CBS
* ABC

Pollster.com has a good summary of how exit polls work.

Contact Info for US Senators

Counties To Watch: Pennsylvania, North Carolina, Nevada and Colorado – Marc Ambinder
FiveThirtyEight.com: Pennsylvania
FiveThirtyEight.com: 538's Battlegrounds as of Mid-September
http://theelectoralmap.com/2008/08/23/geographically-speaking-biden-is-a-smart-choice/
RealClearPolitics – HorseRaceBlog – Swing State Review: Pennsylvania
Open Left:: Top Ten States
Parsing the Pittsburgh Electoral Map « The Electoral Map
A map for victory in the fall and beyond | Redstate
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