Senate sits at 47-53 for Democrats as our House estimate holds near 239 seats

Sixty-one days before the November 3 election, our model gives Democrats a 47 in 100 chance of winning Senate control and Republicans a 53% chance, as of 6:32 AM ET. The mean Democratic Senate outcome in our simulations is 50.1 seats. Democrats need 51 seats for a majority; Republicans need 50, because the vice president is a Republican and a 50-50 tie goes to the Republicans. That arithmetic is why a mean just above 50 seats still leaves the two parties close to even money.

In the House, our model puts the Democratic chance of a majority at 93% and the Republican chance at 7%, with a mean of 239.3 Democratic seats against the 218 needed for control. One caveat is ours to make: our simulation draws correlated error at four levels — national, census division, state and individual district — but not across demographically similar districts in different places, because we have no cluster data for that term. Without it, the House control number is marginally firmer than a fuller decomposition would leave it. We are not putting a figure on the gap.

Our generic ballot average stands at D+6.3, built from 27 polls over the past 45 days. The most recent surveys are broadly consistent with that, with the exception of one house effect. Morning Consult, polling 28,429 registered voters August 24-30, had Democrats at 47.1% and Republicans at 42.3%. YouGov, for the Economist, had Democrats 46-40 among 1,434 registered voters and 36-31 among 1,589 adults, both August 28-31. Ipsos, for Reuters, had Democrats 43-38 among 924 registered voters and 38-31 among 1,167 adults over the same dates. HarrisX and the Harris Poll, for Harvard CAPS, split by population in an August 28-30 survey: Democrats led 51-49 among 2,100 registered voters, while Republicans led 51-49 among likely voters.

The largest single-race move overnight was in OH-7, where our estimate of the Democratic chance fell 23.8 points, from 54% to 30%. Two Senate races moved the other way. In Iowa, the Democratic chance rose 14.9 points to 37% following a Wedgewood Polls survey of 600 likely voters, fielded August 27-29, that had Ashley Hinson at 50% and Josh Turek at 48%. In Michigan, the Democratic chance rose 10.5 points to 69%, alongside Abacus Data polling conducted August 26-28 that had Abdul El-Sayed at 47% and Mike Rogers at 42% among 332 likely voters, and El-Sayed at 41% to Rogers' 35% among 500 registered voters.

Elsewhere on the Senate board, our estimate of the Democratic chance in Virginia fell 9.3 points to 90%, and the New Hampshire estimate fell 10 points to 81%.