With One Week to Go, Democrats Tighten Grip on the House - OZY | A Modern Media Company

With One Week to Go, Democrats Tighten Grip on the House

With One Week to Go, Democrats Tighten Grip on the House

By Daniel Malloy


Nothing is certain, but we have a good idea of how Election Night 2018 will go.

By Daniel Malloy

This election season is roaring to a close with a frenzy of controversy and violence that makes the outcome feel less than certain. But the numbers tell of a hardening reality: a split Capitol come January.

Democrats are deploying a huge cash advantage in the U.S. House to potentially run up the score, while red states are coming home for Republicans in a big way to secure their hold on the U.S. Senate. That’s the latest from OZY’s exclusive election forecast in partnership with Republican data and technology firm 0ptimus, which finds Democrats with a 98 percent chance of taking control of the House, while Republicans have a 90.1 percent chance of holding the Senate with at least 50 votes.

In partnership with Washington-based 0ptimus, we crunched more than 100 factors that helped predict past elections, along with extra weighting for unique aspects of this political year, to produce these forecasts. For more on how these numbers were derived, scroll down to the box below. For more exclusive election coverage, subscribe to our Midterms in a Minute newsletter.


The anticipated gain for Democrats in the House increased by one from last week to a projection of 235 seats on the back of strong new polls and a new round of fundraising reports. Alex Alduncin, data scientist for 0ptimus, points out that in the first 18 days of October, House Democratic candidates outraised Republicans roughly $74 million to $45 million. The numbers are all the more striking because they coincide with a time when Republicans felt an enthusiasm surge from the confirmation of Brett Kavanaugh to the Supreme Court.

Perhaps the GOP surge didn’t show up in money, but post-Kavanaugh polls are fueling Republican Senate gains from Indiana to Missouri to Texas. Our model continues to predict a 52–48 Senate majority for Republicans, even though if you were to give all the races to the party with a greater than even chance of winning, the Senate would be 50–50. “The reason the model thinks this is heading toward 52–48 is because Democrats are dependent on holding or carrying many seats that are uncertain — Arizona, Nevada, Missouri, Indiana, Florida, North Dakota,” Alduncin says. “On average, we’d expect them to lose at least two of those.”

As part of our extensive on-the-ground coverage of races across the U.S. this year, OZY wanted to build a better product to analyze the national political picture — given the failure of such forecasts in the past. So we decided to team up with Washington-based 0ptimus, a Republican firm that developed an unbiased, nonpartisan prediction model to show its clients in both politics and finance where the winds appear to be blowing.

0ptimus’ data team created and tested countless models, crunching publicly available data against past results in House and Senate races. They take into account more than 100 variables, including past vote totals, generic ballot surveys of which party voters prefer in Congress, the unemployment rate, fundraising data and public polling. The firm developed an artificial intelligence system to “smartly” average together several models to produce the strongest prediction numbers for the 2018 elections, automatically testing against past elections to assess quality. You can read more about the 0ptimus methodology here.

Given the unique factors in 2018, we asked 0ptimus to tweak its calculations, adding weight to:

  • The number of small donations — a sign of energy for candidates from Trump to Alexandria Ocasio-Cortez
  • Gender — women are doing exceptionally well this year, and we expect that trend to continue. 
  • Trump’s approval rating — he hangs over the political and media scene with a heavier presence than past presidents.

Meanwhile, we asked 0ptimus to reduce the weight for:

  • Candidate ideology — its calculations rewarded more moderate candidates, while we think this election year is all about firing up the base.
  • Outside money — as OZY has reported, advertising is less persuasive coming from a super PAC than from a candidate.

Because 0ptimus averages several models, it agreed to introduce a new Bayesian model into the mix just for OZY that includes Trump’s approval, gender and unitemized donations while removing one that included ideology and independent expenditures. The result is the numbers we update for you each week.

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