No clue, honestly. Most convenient would be a sudden and meteoric rise from a regional sensation to a national one, like Obama in 08 or Bernie in 16, but one can't count on that, of course. I've got a 'wait and see' attitude as to the 2027-8 primaries, see who declares or seems interested in running before sifting through.
God, I hate that I'm thinking about primaries half a decade out from now.