Older Louisiana poll shows four-point race, forecast stays at 9 in 100

A Public Policy Polling survey of 518 registered voters in Louisiana, fielded July 21-22, put Republican Julia Letlow at 41 percent and Democrat Jamie Davis at 37 percent. On a sample that size, a four-point gap is close, and the poll is best read as showing a race neither candidate had clearly separated in when it was taken.

It did not move our numbers. Our model gives Davis a 9 in 100 chance of winning the seat and Letlow 91 percent, with a mean margin of R+13.5. That is identical to our previous run, earlier on Tuesday afternoon, which also had Davis at 9 percent and the margin at R+13.5. The 5th-to-95th percentile range shifted by a tenth of a point, from R+30.2 to D+3.3 to R+30.3 to D+3.3.

Part of the reason is timing. The poll was fielded in July and reaches us in late September, 40 days before the November 3 election, so it carries less weight than a fresher survey. It is also the second poll in as many days to show a four-point gap here without changing our estimate, which is what a model built on more than one survey should do when new data agrees with old.

The seat is open; Republican Bill Cassidy is the incumbent and is not among the candidates. Nationally, our average of 30 generic-ballot polls over the past 45 days stands at D+8.3, and our Senate estimate gives Democrats a 53 percent chance of winning control, with 51 seats needed. Louisiana is not currently one of the seats carrying that estimate.