Nebraska race tied in new poll; our model widens its range around Ricketts

A new Nebraska Senate poll from Impact Research, fielded August 9-13 among 600 likely voters and reported by omaha.com, put Republican Pete Ricketts at 47 percent and the non-Republican line at 47 percent. The race is even in that survey.

Our model gives Ricketts a 93 in 100 chance of winning the seat. It gives a candidate outside the two major parties — in this race, independent Dan Osborn — a 7 percent chance, and a Democrat a 0 percent chance. The mean margin across our simulations is R+16.4.

The direction of the change is worth separating out. In our previous run, at 4:03 PM ET today, our model gave Ricketts 99 percent and the non-major-party candidate 1 percent, with a mean margin of R+13.9 and a 5th-to-95th-percentile range running from R+24.5 to R+3.3. The new run has a mean margin further toward Ricketts but a wider range: R+34.7 to I+2.4. Our central estimate of the margin moved away from the challenger while the band of outcomes we treat as plausible now extends past even. The probability shift is driven by that widening, not by a tighter center.

The poll itself does not tell a new story. This site reported an even Nebraska survey on August 26, and the Impact Research numbers are consistent with that reading: a race polling close, in a state where our model still expects a wide Republican margin on average.

Nationally, our average of 28 generic-ballot polls over the past 45 days stands at D+6.5. In the Senate, our model gives Democrats a 49 percent chance of winning control and Republicans 50 percent, with a mean of 50.2 Democratic seats. Democrats need 51 seats for control; Republicans need 50, because the vice president is a Republican and a 50-50 tie goes to them.