If Trump wins, the 2028 race will be an epic showdown between Vance and DeSantis. This board, which would have already melted down, will burn a hole all the way to China.

I think Vance is a leading contender in 2028 for the nomination regardless of whether Trump wins or loses.

I think DeSantis is far less likely to be a leading contender in 2028. Unlike Vance, he's going to be out of office - he's term limited and can't run again for governor in 2026, and neither Florida Senate seat is up that year. He displayed a remarkable lack of charisma and proficiency in his 2024 run against Trump, and he'll be several years away from the Covid response that brought him to national prominence. So the torrent of money that flowed to him in his 2024 run is pretty unlikely to be as large in 2028. He's got national name recognition from the 2024 run, and some national support - but it's just hard to see him being the other half of an epic two-person showdown with Vance.