It will be interesting to see how it plays out. As of 2004, I'm not sure the general consensus was that Obama would be the clear candidate in 2008. He did give a great speech, but was still really early in his political career. And as of 2014, nobody would have predicted Trump would so quickly become the face of the GOP. You just never know who is next.It will be a battle. AOC is now old enough to run.
The obvious candidates as of now to try will be Shapiro, Newsom, and AOC. Maybe Buttigieg, Bashear, and Klobuchar throw their hats in the ring, and maybe even Whitmer. There are a lot of candidates who MIGHT seem like possibilities, but it's also possible that the candidate hasn't even emerged yet.
But I think a big thing is going to be starting to win the narrative on relevant media streams moving forward. Without that, I think it's going to be an uphill battle.