Grab your pencils, break out the brackets, circle the favorites and start hunting for upsets.
No, March hasn’t returned early. But NASCAR’s In-Season Challenge is back, bringing with it a five-race, $1 million head-to-head knockout tournament in the middle of the NASCAR Cup Series’ summer stretch. And if last year’s inaugural edition of the Challenge was any indication, we could be in for some wild happenings — even if it’s unlikely we’ll see a 32-seed like Ty Dillon go all the way to the final again. (Never say never!)
Here are the initial odds to advance through each round and win the 2026 Challenge, according to my Cup Series forecast model (which uses track type-specific ratings for each driver to simulate the rest of the schedule 10,000 times, tracking who will win The Chase, or — in this case — the In-Season Challenge):
With those numbers in place as a framework, let’s dive into the drivers to watch — from the safest picks at the top of the board to the bracket-busters capable of making some madness out of June and July, too:
The Favorites
Unsurprisingly, the leading favorites to win the 2026 In-Season Challenge are the same guys who are the favorites to win the 2026 Cup Series title overall: Denny Hamlin and Tyler Reddick. It’s fascinating that the same dynamic dominating the regular-season stretch-run conversation — whether Reddick can hang on to his commanding early-season lead for the top seed in The Chase — will also run in parallel during the In-Season Challenge. While the two cannot meet until the final (and there’s only a 6-7% chance both would survive that long), the odds are 61% that both will make the Round of 16, 35% that both will make the quarterfinals and 19% that both will make the semifinals.
As always, some of that comes down to who can do well on the other driver’s track-type forte — Hamlin on road courses, Reddick on short tracks — but that factor is mitigated some by bracket paths, as Hamlin gets the much more favorable first-round draw of Ty Dillon (unless we think his head-to-head speedway upset of Denny last year was repeatable) for Sonoma, compared with Reddick getting the theoretically more dangerous opponent of Alex Bowman (even if Bowman’s road-course form this year needs work). As such, it’s kind of a dead-heat as to whether the No. 11 or the No. 45 is more likely to claim the $1 million prize when the confetti clears at the Brickyard.
Of course, there is also another group of drivers lurking just outside the top two, led by Ryan Blaney and Kyle Larson. Again, these are also the next-most likely drivers to win The Chase — maybe the only ones who realistically have a shot at unseating Reddick and Hamlin — but they also will have a chance to audition for it early in this stage.
Blaney drew Josh Berry on a Round 1 road-course, making him the single biggest favorite this week, and he will almost certainly get Shane van Gisbergen at Chicagoland, where the No. 12 will be a big favorite. Larson, meanwhile, drew the improving Riley Herbst for Sonoma and probably will get teammate William Byron in a big-name Hendrick Motorsports showdown for a spot in the quarterfinals — a tougher path, but one that would make him a serious title threat if he gets past Blaney (or someone else) in the quarterfinals.
The Dark Horses
There is a gap to the next group in the odds, though not a massive one. The dark-horse drivers are the ones outside the obvious favorites, whose numbers suggest they may still be capable of a deep run.
The leaders here are Chase Elliott, Mr. Consistency, and Ty Gibbs, the defending champ. Both are capable of winning it all, though the bracket has the potential to hand them eerily similar obstacles early in the run: In each case, Gibbs and Elliott ought to handle their first-round opponents (Austin Dillon and Noah Gragson, respectively), but the other part of their “pod” offers a dangerous, underseeded driver (Chase Briscoe and Bubba Wallace) who must get past a road-course veteran (AJ Allmendinger and Michael McDowell) at Sonoma to advance. Whichever one doesn’t have to face Briscoe or Bubba at Chicagoland might be the winner here.
Our next tier of sleepers includes Briscoe, Byron, Christopher Bell, Chris Buescher, Wallace and Carson Hocevar, all of whom are packed between 3-5% odds heading into the tournament. Among those, Byron and Buescher are much safer bets to make the Round of 16 — facing John Hunter Nemechek and Ricky Stenhouse Jr., respectively — while the rest face tougher first-round draws, but all would be dangerous if they advance. And in fact, Bell and Buescher are on a second-round collision course if things go chalk, with the winner having legitimate potential to knock out Hamlin early.
The Tough Draws
With the seeding fixed to reflect the actual standings — one of my top suggestions coming out of last year’s tournament — immediate draws begging for an upset are tougher to find. But that doesn’t mean they don’t exist. No. 15 seed Erik Jones got stuck with three-time Cup champ Joey Logano in Round 1, making Jones an underdog in the model, even though Joey is having arguably the worst season of his career. Jones has been doing very well recently, but at a road course — not his specialty — that may not be enough to dispatch Logano.
Similarly, Wallace, Hocevar and Bell drew rough first-round matchups — McDowell on a road course, Zane Smith and Ross Chastain, respectively — making each a coin flip at best to advance out of the gates. Smith’s recent uptick in performance mirrors Hocevar’s, and the No. 38 has been substantially better on road/street tracks this year than the No. 77. And while Bell has more contender cachet, he’s also dealing with an injury, while Chastain has been better on road courses this year (79.3 Driver Rating versus 62.7 for Bell).
The Spoilers
The flip-side of a tough draw is a lower-seeded driver with a shot at knocking off the favorite, so we can immediately mark down Logano, McDowell, Smith and Chastain as leading candidates to end promising Challenge runs before they even get a chance to begin.
But they’re not the only ones with a shot at shaking things up for the favorites. Allmendinger is always a threat on road courses, so he could take out Briscoe at Sonoma. Likewise, No. 17 seed Brad Keselowski (facing No. 16 Austin Cindric), No. 19 Ryan Preece (No. 14 van Gisbergen) and No. 25 Todd Gilliland (No. 8 Daniel Suárez) all have at least some chance of beating their higher-ranked first-round foes, with Herbst (facing Larson) not too far behind.
(If last week proved anything, it’s that even SVG can be beaten in a single road-course race, as he got caught up in chaos in front of him in San Diego and saw his day end early.)
And stop us if you’ve heard this one before — but Logano, as the 18-seed, has the best chance to spoil the whole championship for the top seeds, with the highest odds to advance past the Round of 8 and win the title of anybody seeded outside the top half of the bracket. (Followed by, of course, fellow chaos agent Chastain.)
The Cinderellas
If you’re looking for this year’s Ty Dillon, though — say, a driver seeded 24th or worse with some kind of chance to crash the final four party — you have a few options.
No. 27 Riley Herbst and No. 28 Austin Dillon (speaking of NASCAR’s all-time chaos agents) each have a 3% chance to make the last quartet of drivers standing, despite some staunch competition looming early in the bracket. No. 32 Alex Bowman is hardly this field’s “Mr. Irrelevant,” either, as he has a 5% shot at the semifinals despite facing No. 1 seed Reddick in Round 1. (Both have won on road courses, for what it’s worth.)
And maybe the best Cinderella pick of all is No. 24 Zane Smith, who has a whopping 8% chance to make the semifinals despite his low seed. Smith is bolstered by a number of factors, including his edge on road courses over first-round foe Hocevar, a fairly soft second-round path (against the Suárez/Gilliland winner), catching Reddick — if chalk holds — at a drafting track (EchoPark) in the Round of 16, and the possibility of facing only one true short-track ace (Gibbs) at North Wilkesboro Speedway, if things come down to that.
A lot of moving pieces need to fall into place for all of that to happen, but Smith’s path to a deep In-Season Challenge run is surprisingly plausible when laid out that way. Or who knows? Maybe the tournament will just belong to Ty Dillon again — this time armed with an even better seed (31 versus 32) than he had a year ago.
