Stella Lefty’s “Boston” commands the market’s 91% implied probability for the Billboard Hot 100’s No. 2 spot the week of September 12 because it just notched a new peak at No. 2 on the Aug. 29 chart, driven by surging multi-format radio impressions, steady streaming gains, and broad country-pop crossover appeal. The track’s interpolation of Noah Kahan’s “Stick Season,” combined with strong social momentum and regional radio dominance, has kept it ahead of recent challengers like Taylor Swift’s “I Knew It, I Knew You” and Morgan Wallen’s “Been By Now.” With weekly chart updates and potential new releases or streaming spikes as the primary swing factors, an upset would require another title to post outsized gains in the final tracking days or for “Boston” to see a sudden drop in airplay or consumption.