The most recent high-quality PA polls, Washington Post-ABC and New York Times/Sienna both have Trump behind by 9 points in the states.
The key: (from Aaron Blake of the Post)
Trump’s erosion is...particularly pronounced among White Americans with college degrees....Biden [in Pennsylvania] now leads by 23 points in the Post-ABC poll (61 to 38) and by 26 points in the NYT-Siena poll (59 to 33).
But it’s not just among college-educated Whites; it’s also among noncollege-educated Whites. Although Trump carried them by 32 points in 2016 (64 to 32), he currently leads by 13 in the NYT-Siena poll (52 to 39) and 17 in the Post-ABC poll (58 to 41)."
Martin Longman of the Washington Monthly adds:
"Trump is severely underperforming in Western Pennsylvania, the region I pegged as most responsible for his surprise victory in my Washington Monthly piece How to Win Rural Voters Without Losing Liberal Values. Excluding Pittsburgh’s Allegheny County, Trump carried this region four years ago by 29 points. The Washington Post-ABC poll has him leading there by three."
The death march continues.