Democrats near even in Senate, 94 in 100 in House with 75 days left

Seventy-five days from the November 3 election, our model gives Democrats a 49 in 100 chance of winning Senate control and Republicans a 51 percent chance, as of 6:30 AM ET on August 20. The mean Democratic seat total in our simulations is 50.2. Democrats need 51 seats for a majority; Republicans need 50, because the vice president is a Republican and a 50-50 tie goes to their side. That asymmetry is why a projected seat average above 50 still leaves the chamber close to even.

In the House, our model gives Democrats a 94 percent chance of a majority, against 6 percent for Republicans, with a mean of 242.6 seats and 218 needed for control. Our national average of the generic congressional ballot is D+6.7, drawn from 25 polls fielded in the past 45 days. One caveat belongs on the House number. Our simulation draws error at four correlated levels — national, census division, state and individual district — but not at the level of demographically similar districts scattered across different states, because we have no cluster data for that term. The omission leaves our House control probability marginally firmer than a fuller decomposition would. We are not in a position to say by how much.

Ohio produced the largest move away from the Democrats among Senate races, with the Democratic win probability down 6.5 points to 60 percent. A Wedgewood Polls survey of 800 likely voters, fielded August 11-13, put Sherrod Brown at 48 percent and Jon Husted at 44 percent. Louisiana fell 8.3 points to a 2 percent Democratic chance. In the other direction, Alaska rose 7.1 points to 30 percent and Maine rose 6.4 points to 81 percent. Arkansas sits at 5 percent after a 4.6-point rise, and the state's two most recent polls disagree: J.L. Partners found Tom Cotton at 51 percent and Hallie Shoffner at 35 among 803 likely voters August 14-18, while Hendrix College found Shoffner at 47 and Cotton at 44 among 1,217 likely voters August 11-12. Michigan, where our forecast moved 15.9 points to 58 percent Democratic earlier this week, has not moved further since.

Elsewhere in recent Senate polling, InsiderAdvantage surveyed 800 Georgia likely voters August 16-17 and found Jon Ossoff at 50 percent and Mike Collins at 43. KTSP/SurveyUSA polled 661 Minnesota likely voters August 13-17, with the Democrat at 46 percent and the Republican at 41. UMass Amherst/YouGov surveyed 800 Massachusetts registered voters August 5-12 and found Ed Markey at 51 percent to John Deaton's 30. Two Michigan polls from TIPP Insights, fielded August 6-10, put Abdul El-Sayed at 45 percent to Mike Rogers's 42 among 1,215 likely voters and at 43 to 39 among 1,528 registered voters; Susquehanna Polling & Research had El-Sayed at 46 and Rogers at 39 among 800 likely voters August 11-17. Idaho drew two surveys with little in common: Peak Insights, polling 500 likely voters August 11-13, put Jim Risch at 52 percent and independent Todd Achilles at 18, while The Bullfinch Group, polling 608 likely voters on August 13, had Risch at 34 and Achilles at 30.