Big Data Poll puts Cooper up 12 with likely voters as our forecast edges to 95 percent

Roy Cooper leads Michael Whatley by double digits in two new readings of the North Carolina Senate race, both from the same Big Data Poll survey sponsored by the Public Polling Project and fielded September 27-29. Among 642 likely voters, Cooper has 50.8 percent to Whatley's 38.5 percent, a 12.3-point gap. Among 698 registered voters, Cooper has 49.3 percent to Whatley's 37.8 percent, an 11.5-point gap.

Our model now gives Cooper a 95 in 100 chance of winning the seat, up from 94 percent in the run earlier this morning. Our projected margin moved from D+8.9 to D+9.1. The new polls confirm the race's shape rather than change it. The previous run already had Cooper as a clear favorite.

Both samples come from one survey, so they are not two independent confirmations. Each runs a few points ahead of our projected margin, which accounts for the small upward move.

The range of outcomes our model considers plausible remains wide. Its 5th-to-95th percentile span now runs from R+0.1 to D+18.2, compared with R+0.3 to D+18.0 before. Whatley's chance in our model is 5 percent.

The seat is open. Republican Thom Tillis is not on the ballot. Nationally, our model gives Democrats a 53 percent chance of winning Senate control, which requires 51 seats for them. Republicans need 50, because the vice president, a Republican, breaks a 50-50 tie. Our model's average outcome is 50.5 Democratic seats.