Monmouth University published a poll today showing that the post-convention race is getting tight in Pennsylvania. This is a substantial change from where the race was polling just six weeks ago:

Among all registered voters in Pennsylvania, the race for president stands at 49% for Biden and 45% for Trump. Another 2% support Libertarian Jo Jorgensen, less than 1% back the Green Party’s Howie Hawkins, and 4% are undecided. Voter intent includes 43% who say they are certain to vote for Biden (versus 44% who say they are not at all likely to support the Democrat) and 40% who are certain to support Trump (versus 47% who are not at all likely).

The contest tightens when different likely voter models are applied. A model based on a somewhat higher level of turnout than 2016 puts the race at 49% for Biden and 46% for Trump, while one reflecting lower turnout has it at 48% for Biden and 47% for Trump.

So depending on what type of turnout you have this is either a 3 point race or a 1 point race. Just six weeks ago, Biden held a 13 point lead among registered voters which worked out to a 10 or 7 point lead among likely voters depending which turnout model you use. In other words this looks like a 6 point drop for Biden in 6 weeks. The margin of error on this poll is 4.9 percent. The shift in the numbers has come mostly from men who were pretty even split in the prior poll and now favor Trump heavily:

Biden maintains a solid 59% to 35% lead among women (similar to 60% to 34% in July), but he has lost ground among men. They prefer Trump by 56% to 37%, compared with a much closer 47% to 45% margin in July.

There’s also a pretty big difference in the level of enthusiasm in each party:

Republican voters (51% now; 42% in July) continue to be much more likely than Democrats (26% now; 18% in July) to say they are very optimistic about the 2020 presidential election. They have also caught up on the metric of feeling more enthusiastic about this contest compared to past elections (52% Republicans and 49% Democrats now; 42% Republicans and 53% Democrats in July).

Finally, the coalition of minority voters that is key to Democratic prospects is still overwhelmingly behind Biden, but their support appears to be softening. Monmouth puts that down to successful outreach during the RNC:

Voters of color have become somewhat less certain of their choice. Biden maintains a sizable lead with this group (72% to 15% versus 76% to 16% in July), but a larger number are now undecided (9% now versus 3% in July).

“The Republican convention attempted to sow some seeds of doubt among core Democratic blocs, especially young and urban voters. It looks like they may have had a small amount of success with that, at least for now,” said Murray. Interviewing for the poll started on Friday after the RNC, with most being completed before Biden’s speech in Pittsburgh on Monday.

All of this helps explain why Biden made that trip to Pittsburgh Monday. What was looking like a solid win in July is now a neck and neck race. Having watched the speech, complete with technical glitches and sentences that went nowhere, I’m not sure it helped him that much.

There is some good news for Biden in this poll though. He’s leading Trump on the issue of handling race relations (obviously a big one at this moment) by about 11 points. The poll also shows that President Trump is underwater on his handling of the coronavirus, which explains why Biden pivots to this issue every time he’s asked about rioting and looting.

To close this out, here’s Nate Silver’s take on this poll:

Not so hot for Biden here, whose Pennsylvania numbers have been worse than you might have expected all year (WI and MI have often been better for him, by comparison). Monmouth's July numbers were an exception to that, but this poll isn't. https://t.co/L3fk9fGHoC

— Nate Silver (@NateSilver538) September 2, 2020

Biden now +4.2 in our Pennsylvania polling average, which is now the same as in Florida (+4.2). These are the most common tipping-point states. By comparison, he's at +7.1 in our national average, so we see the same 3-point gap as in 2016. https://t.co/wKbW02AGO5 pic.twitter.com/pGUrl77ncQ

— Nate Silver (@NateSilver538) September 2, 2020

Arizona also polling at Biden +4.0, so based on polling averages alone, it's basically in a 3-way tie with PA and FL for being the tipping-point state. That could potentially yield this map where Biden wins 270-268. pic.twitter.com/pecIcXjioJ

— Nate Silver (@NateSilver538) September 2, 2020