Oklahoma Senate polls show Hern up more than 20, and our forecast barely moves

Two new surveys of the open Oklahoma Senate race point the same direction. CHS & Associates, polling 500 registered voters August 3-6, had Republican Kevin Hern at 48 percent and the Democrat at 27 percent. A second CHS & Associates survey of 500 registered voters over the same August 3-6 window had Hern at 49 percent and the Democrat at 25 percent.

Our forecast now gives Hern a 99 percent chance of winning the seat and the Democrat a 1 in 100 chance, with a mean margin of R+28.7. The run before this one, from 10:30 a.m. ET on August 21, had the same win probabilities and a mean margin of R+28.5. The 5th-to-95th percentile band moved from R+47.7 to R+9.2 to R+48.2 to R+9.2. In other words, the new numbers confirmed what the model already had rather than changing it.

Both polls leave a substantial share of respondents unallocated — 25 percent in the first, 26 percent in the second — and both are of registered rather than likely voters. Our mean margin sits wider than either poll's margin, and the low end of our range, R+9.2, is narrower than both.

Nationally, our average of 24 generic-ballot polls over the past 45 days stands at D+6.7. In the Senate, we give Democrats a 47 percent chance of winning control and Republicans 53 percent, with a mean of 50.2 Democratic seats; Democrats need 51 seats for control, Republicans 50, because the vice president is a Republican and a 50-50 tie goes to the Republicans. In the House, we put the Democratic chance of a majority at 94 percent, against 218 seats needed and a mean of 242.5. That House figure is marginally firmer than it should be: our simulation correlates error nationally, by census division, by state and by district, but we have no cluster data to correlate demographically similar districts across the map.