Nate Silver’s forecast moved Democrats’ chance of winning the Senate to 58.6% on Monday, which makes them favorites, but you should read that number as a bet on five close races breaking the same way rather than as a map that has turned blue.
- Republicans hold the Senate 53 to 47, so Democrats need a net gain of four seats to take the majority.
- The Silver Bulletin forecast had fallen as low as 51.1% earlier in the week before a run of polls pushed it back up, including James Talarico leading by 2 to 5 points in Texas, Sherrod Brown up 4 in Ohio and an 8-point Democratic lead on the generic ballot.
- Decision Desk HQ’s model is more cautious at 52% and rates Texas, Ohio, Alaska, Maine and Iowa as toss-ups, with no Democrat above 59% in any of them.
| Forecast | Democrats’ chance of a Senate majority | As of |
|---|---|---|
| Silver Bulletin | 58.6% | Sept. 14 |
| Polymarket traders | About 54% | Sept. 15 |
| Decision Desk HQ | 52% | Sept. 14 |
| Decision Desk HQ race odds, if the races were unrelated | 36% | LNC calculation |
The bottom row uses Decision Desk HQ’s own odds for eight races (North Carolina, Texas, Ohio, Alaska, Maine and Iowa to flip; Georgia and Michigan to hold) and assumes each is decided independently.
The bottom row is the one worth sitting with, because it shows you what “favored” is actually built on. Decision Desk HQ gives Democrats a 77% chance to flip North Carolina, an 83% chance to hold Georgia and a 66% chance to hold Michigan, plus the five toss-ups. If every one of those races were settled on its own, like eight separate coin flips with slightly different weights, Democrats would reach a net gain of four seats only about 36% of the time. The models land well above that because they assume the races move together: a national environment good enough to carry Talarico in Texas is probably good enough to carry Brown in Ohio. That assumption is what turns a long shot into a favorite, and it is also why the same forecast can swing more than seven points in a single week.
Part of that swing is not voters changing their minds. Silver wrote that “more pollsters switch their likely voter models back on, which is helping Democrats,” which means some of the September movement reflects a change in who pollsters are counting. That is a legitimate adjustment, since likely voters are the people who decide a midterm, and traders on Polymarket price Democrats at about 54%, close to the models. But it tells you part of the jump from 51.1% to 58.6% is pollsters catching up with the electorate, not the electorate moving toward Democrats.
Our read is that “favored” is the right word and “flip” is premature. Democrats have a real path because Republicans handed them one, most visibly when Texas primary voters chose Ken Paxton over John Cornyn, a senator who had never lost a statewide race. Anyone calling this a wave is ignoring the distance between 36% and 58.6%, and that distance is a single assumption about a national mood holding for seven more weeks. Watch whether the Texas, Ohio and Alaska polls keep moving together through October. If they start to split, the forecasts will slide toward that bottom row, and the Senate will look like what it has been all year: a coin flip with a thumb on the Democratic side.