According to this[0], Coke (the cola brand, not the company) has a ~19% soft drink market share in the US vs. Pepsi at ~8%. This[1] has Coke (the company, not the cola brand) at a 69% market share of the US soft drink market vs. Pepsi 15 27%. Pepsi is a larger company, though, because they own a bunch of snack food brands whereas Coke is beverages only.

0: https://www.wfaa.com/article/news/local/us-soda-rankings-cok... 1: https://www.investopedia.com/ask/answers/060415/how-much-glo...