What Five Major Forecasts Say About Republican Chances of Losing the Senate - Newsweek

Republicans are defending a 53-47 Senate majority this November, and for most of the past year, forecasters treated that math as close to settled. Democrats need to flip at least four Republican-held seats without losing any of their own, in a map that is offering them few obvious targets.

A string of strong generic ballot polls for Democrats, shifting ratings in New Hampshire and Ohio, and a widening gap between rival forecasting models have turned a race that once looked like a formality for the GOP into one of the more genuinely uncertain Senate cycles in years.

Whether that uncertainty reflects real movement in the electorate, a temporary polling mirage, or Democrats simply repeating overperformances that evaporate on Election Day is the question hanging over the 2026 midterms.

Here is what five of the most closely watched forecasts say right now, and why they do not all agree.

Cook, widely considered the industry standard for nonpartisan race ratings, currently lists seven of the 35 Senate seats on the ballot as toss-ups: Alaska, Iowa, Maine, Michigan, New Hampshire, Ohio and Texas. The other competitive races are Georgia and North Carolina, which Cook rates as lean Democrat.

The biggest recent change came in New Hampshire, where Cook moved the Senate race from "lean Democrat" to "toss-up" on September 15. The race is between Democratic Representative Chris Pappas and former Republican Senator John E. Sununu, who is seeking a return to the Senate nearly two decades after leaving office.

The shift makes the race more competitive for Democrats as they look for seats to defend and opportunities to gain elsewhere.

The seven toss-up races also show the range of candidates running this cycle. In Michigan, former Wayne County health director Abdul El-Sayed defeated Representative Haley Stevens in the Democratic primary and now faces former Republican Representative Mike Rogers. Rogers lost the same open seat by less than a point in 2024.

In Iowa, Representative Ashley Hinson is defending the seat of retiring Senator Joni Ernst against state Representative Josh Turek, a Paralympic gold medalist. Turek has run closer than expected in a state President Donald Trump carried by 13 points in 2024. Cook moved the race from lean Republican to toss-up in August.

In Texas, Attorney General Ken Paxton, who defeated Senator John Cornyn in a Republican primary runoff after receiving Trump's endorsement, faces state Representative James Talarico for the seat Cornyn is leaving. Cook also moved that race from lean Republican to toss-up in August.

The races with incumbents have their own challenges. Senator Susan Collins of Maine is seeking a sixth term against Troy Jackson, a former state Senate president who became the Democratic nominee in late July after primary winner Graham Platner withdrew amid sexual assault allegations.

In Ohio, appointed Senator Jon Husted, who took the seat after JD Vance became vice president, faces former Senator Sherrod Brown, who is seeking a return to the Senate after losing his reelection bid in 2024.

In Alaska, Senator Dan Sullivan faces former Representative Mary Peltola in a four-way race that will be decided using ranked-choice voting.

The University of Virginia's Crystal Ball, edited by political analyst Larry Sabato, rates five Senate races as toss-ups, one fewer than Cook, after moving Texas from "lean Republican" in late August.

In a September analysis, managing editor Kyle Kondik wrote that Republicans "probably retain a slight edge" in the Senate, but called that assessment harder to defend than at any point this cycle, citing President Trump's approval rating slipping underwater in red states hosting key races.

Kondik's own best guesses on the five toss-ups, taken individually, add up to a 50-50 Senate, decided by Vice President JD Vance's tie-breaking vote in Republicans' favor. He flagged Ohio and Iowa as the two races where he worries most about polling overstating Democrats, even as Sherrod Brown leads most Ohio surveys.

He also described Texas Attorney General Ken Paxton as a weak nominee that Republicans would still rather run than Democratic state Representative James Talarico, and noted that outside Republican money has started arriving late to defend him.

FiftyPlusOne, built by a team of former FiveThirtyEight journalists, gives Democrats a 65 percent chance of winning Senate control as of Wednesday. Its median simulated outcome is a 51-49 Democratic Senate, exactly the net gain of four seats Democrats need.

The model's race-by-race breakdown looks calmer than Cook's or Crystal Ball's, rating only two seats true toss-ups. It has Iowa tied at 50-50 between Hinson and Turek, and it gives Democrat James Talarico a 60 percent edge over Attorney General Ken Paxton in Texas. That Texas number is the outlier of the whole roundup.

FiftyPlusOne rates four seats "lean Democrat" and three "likely Democrat," giving Democrats a cushion in races other forecasters still call competitive.

Decision Desk HQ says Democrats are narrowly favored to win the Senate, giving them a 51 percent probability to Republicans' 49 percent as of Wednesday morning. Its median outcome, drawn from 1 million simulations, comes out to a 51-49 Democratic Senate, just enough for control.

The site's own tracking chart shows how recent that shift is. As late as July 24, Decision Desk HQ had Republicans favored 60 percent to 40 percent. That lead eroded through August and flipped in early September, with the two lines crossing and settling into the current 51-49 Democratic edge.

Decision Desk HQ counts five toss-ups: Maine, Ohio, Texas, Iowa and Alaska, two fewer than Cook. Iowa is the one race in that group where it leans Republican, giving Ashley Hinson a 55 percent edge. In the other four, the Democratic candidate is ahead: Troy Jackson at 53 percent in Maine, Sherrod Brown at 54 percent in Ohio, James Talarico at 54 percent in Texas and Mary Peltola at 59 percent in Alaska.

Nate Silver's new midterm model, called FLIPR, is where the picture starts to diverge sharply from the qualitative handicappers. As of September 15, FLIPR put Democrats' chances of retaking the Senate at 59 percent, the highest mark of the cycle so far.

Silver's model tied the jump to a run of strong polling for Democrats, including a New York Times/Siena poll showing the generic ballot at Democrats plus 8 and a YouGov/Economist poll showing it at Democrats plus 12 among likely voters.

FLIPR runs 40,000 simulations daily and models the Senate, House and governors' races jointly, which lets it calculate scenarios like Republicans holding the Senate while losing the House.

Newsweek’s reporters and editors used Martyn, our AI assistant, to produce this story. Learn more about Martyn here.

Contact Newsweek editors on this story: Jason Lemon and Gray R. Thomas