New PA-1 poll shows a close race, and our forecast does not move

One new poll in Pennsylvania's 1st District has the Republican at 47 percent and the Democrat at 43 percent. It was conducted by Global Strategy Group among 500 likely voters, fielded August 5-9. With a sample that size, a four-point margin describes a close race rather than a settled one.

Our forecast did not move. The model gives the Democrat a 37 in 100 chance and the Republican 63 percent, the same split as our previous run earlier this morning. The mean margin is R+3.5, against R+3.4 before. Our 5th-to-95th-percentile range runs from R+20.5 to D+13.5, essentially unchanged from the R+20.4 to D+13.7 we had at 8:30 a.m. ET. The new survey is close enough to what the model already expected in this district that it confirms the prior rather than shifting it.

The wider environment in our numbers leans toward Democrats. Our generic-ballot average, drawn from 25 polls over the past 45 days, stands at D+6.7. In the House, our model puts the mean Democratic seat count at 242.4 against the 218 needed for control, and gives Democrats a 93 percent chance of winning a majority. PA-1 is one of the seats our model treats as competitive but tilting Republican, which is why a national edge of that size does not translate into a favorite here.

One caveat on the House figure. Our simulation draws correlated error at four levels: national, census division, state, and each district on its own. It does not include a term linking demographically similar districts wherever they sit on the map, because we have no cluster data to build one. That omission makes our House control probability somewhat firmer than a fuller model would produce. We are not putting a number on the gap, because this run does not measure it.