Field of 16: Path to 16 unique winners still in play

On one hand, the Cup Series playoff picture is pretty set in stone. [caption id="attachment_481343" align="alignright" width="394"]Playoff Probabilities provided by Racing Insights (entering Iowa)[/caption] Chris Buescher holds the 16th and final spot for the postseason by 42 points over RFK Racing teammate Ryan Preece. That's nearly a race in hand while Tyler Reddick (plus-138) and Alex Bowman (plus-63) are sitting pretty as the current field is. However, the other hand says the final four races of the regular season could all produce unique winners with just three spots up for grabs. Preece is an Xfinity Series winner at Iowa. Michael McDowell and AJ Allmendinger will be in the mix of competitors who could win at Watkins Glen. Austin Dillon won at Richmond in controversial fashion, but was on his way to Victory Lane without it becoming encumbered if there wasn't a caution in the closing laps. The regular-season finale at Daytona can produce a winner from anybody in the field, so while a long shot, there's a realistic chance for huge surprises before the postseason begins at Darlington. Let's take a look at the latest playoff probabilities provided by Racing Insights and which drivers are in a good or compromising spot for Iowa Speedway on Sunday (3:30 p.m. ET, USA Network, HBO Max, MRN Radio, SiriusXM NASCAR Radio, NBC Sports App). RELATED: Iowa schedule | Cup Series standings GREEN FLAG [Who's in a great spot for Iowa] Preece (6.33% playoff probability) is coming off a top-five run in the Brickyard 400 and will enter a track he's won at with plenty of momentum to finally break through for his first Cup triumph. On paper, a 42-point gap to make up wouldn't be considered a "great spot," but Iowa is certainly a track that the No. 60 team has circled to perform at its best. Alex Bowman (74.88% playoff probability) should continue to increase his cushion on Sunday. He's finished top 10 in four of the last five races and put together an eighth-place run last year at Iowa amid an event where three of the Hendrick cars finished inside the top 10, while Kyle Larson wrecked out early after leading 80 laps and grabbing a stage win. YELLOW FLAG [Who's on the fringe for Iowa] This is going to Tyler Reddick, who should still be considered a playoff lock with a 97.89% probability to make the 16-driver field. The No. 45's playoff hopes simply come down to no one outside of the bubble stealing a win. Reddick would love to win before the postseason begins, but sitting sixth overall in points is nothing to scoff at. The sour note for Reddick entering Iowa is that smaller tracks are a vulnerable spot for the California native. 23XI Racing did not show great speed in last year's inaugural event in The Hawkeye State as Reddick finished 22nd and Bubba Wallace tallied a 17th-place result. RACING INSIGHTS: Full race projections for Iowa RED FLAG [Who I'm concerned about heading to Iowa] This spot goes to Buescher simply for where he's positioned in the playoff picture. It's the ultimate conundrum for RFK as two of its cars sit 16th and 17th while co-owner Brad Keselowski lurks to possibly knock both out of the top 16. Buescher was also not fast at Iowa last year as he placed 18th.