Cillizza's midterm metrics: Sizing up the Senate with seven days to go

By now, everyone has sliced and diced the Senate map in a thousand different ways.

Toss Up! Lean Democrat! Likely Republican! The 10 races most likely to switch parties! (I did that one myself!) The most expensive races in the country! The best candidates! The worst candidates!

So, with only a week(!) left before the midterms, I thought I would turn to the Kalshi midterm elections hub to see where traders see the individual Senate races.

As in, which races have the tightest markets? And, by way of looking forward, are those the races that will be the closest – in terms of winning margin – in seven days time?

It’s an interesting thought experiment, right?

Let’s do it.

By my count, there are 11 Senate races (out of 35 total contests) where one of the candidates doesn’t have a 90% or higher probability of winning in the Kalshi markets right now.

That 90% and above territory includes plenty of races no one thought would ever be competitive – like Sen. Mark Warner’s reelection bid in Virginia (98%) — as well as a bunch of races most everyone thought would be far tighter including Georgia Sen. Jon Ossoff’s race (94%) and the open Republican seat of retiring Sen. Thom Tillis (97% Democratic pickup)

Here are the 11 most competitive Senate race markets on Kalshi – ranked from the most divided probability (closest to 50-50) to the least. 

I have said for months that the race between Republican Rep. Ashley Hinson and Democratic state Rep. Josh Turek is the linchpin on which the Senate turns. If Hinson wins, I think Democratic gains top out at about 51/52 seats. If Turek wins, I think Democrats could get to 54 or even 55 seats. The market here has been steadily narrowing for months, with Turek slowly climbing into the low 40s in terms of win probability.

A few weeks back Democrat Troy Jackson was a clearer favorite here. Why has the market tightened? A few things: a) independent polling continues to show Republican Sen. Susan Collins within striking distance b) the realization that Jackson is a “meh” candidate has set in and c) Collins’ long history of over-performing GOP baselines – and expectations – has made Democrats very jumpy.

The sleeper race of the cycle is no longer a sleeper. Everyone – including exasperated Republican strategists – admit that Sen. Roger Marshall let his guard down and has now put a state (and a seat) in play that Democrats haven’t won since 1932. One of the challenges of trading or handicapping this race? There’s just a very limited number of competitive statewide federal elections in Kansas to look back to for wisdom!

This is, by far, the most heavily traded Senate market. Everything is bigger in Texas, after all! Of late, James Talarico’s number in the market has slipped slightly. I think that makes sense given that Texas IS a Republican state. (Donald Trump won by 14 points in 2024.) And that means that the polls (and the markets) tighten as Republicans start to come home to Ken Paxton.

If Texas is the biggest race of 2026, Michigan is a very close second.  Many Democrats are looking to Abdul El-Sayed’s candidacy as a litmus test as to whether a candidate with clear Democratic Socialist leaning – AES is not, technically, a Democratic Socialist – can win a swing state general election race. And there’s no one Republicans (and Trump) want to beat more than El-Sayed.

Honestly, I was a little surprised that this market is as competitive as it is. To me, former Democratic Sen. Sherrod Brown is a clear favorite over appointed GOP Sen. Jon Husted – and that was before Vivek Ramaswamy tanked the Republican brand in the state with his despicable ad.

If I was shocked by how split traders are in the Ohio market, I am equally surprised that there appears to be so much certainty – three in four chance! – about former Democratic Rep. Mary Peltola’s chances of winning. Yes, she’s ahead of GOP Sen. Dan Sullivan. But with four candidates on the general election ballot and the winner decided by ranked-choice voting I feel like there is a lot of uncertainty left here.

There’s a new (Democratic) poll out this week that shows independent Dan Osborn leading Republican Sen. Pete Ricketts 48% to 41%. Count me very skeptical on that one. I think Osborn has a shot – he came within seven points of winning in a far worse national environment in 2024 – but there’s no way that even if he wins it’s by seven points.

A month ago, South Carolina Sen. Darline Graham had an 87% probability of winning. And it just keeps dropping. Which makes sense! Trump doesn’t just campaign in state in the final two weeks of the midterms if the race isn’t close. Nor does the main GOP Senate super PAC spend millions of dollars on a race they aren’t afraid they might lose.

In a slightly-less-good national year for Democrats, I think Democratic Lt. Gov. Peggy Flanagan could lose to former sports broadcaster Michele Tafoya. But man, it’s tough – even with the Tim Walz administration fraud scandal still percolating in the state. My guess is Tafoya loses this race and immediately starts running for the seat that Sen. Amy Klobuchar will vacate when she is elected governor in November.

This race between appointed Sen. Ashley Moody and Democratic state Rep. Angie Nixon barely makes it under my 90% cutoff. (Moody has been over 90% as recently as October 23 so…) This is a race that only comes home for Democrats if they are winning everywhere else. 

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